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BaseRepresentation
bin1110011010101
3101010101
41303111
5214011
654101
730343
oct16325
911111
107381
115600
124331
13348a
142993
1522c1
hex1cd5

7381 has 6 divisors (see below), whose sum is σ = 8246. Its totient is φ = 6600.

The previous prime is 7369. The next prime is 7393. The reversal of 7381 is 1837.

7381 = T31 + T32 + ... + T41.

7381 is nontrivially palindromic in base 3 and base 9.

7381 is an esthetic number in base 3, because in such base its adjacent digits differ by 1.

7381 is a nontrivial binomial coefficient, being equal to C(122, 2).

It is an interprime number because it is at equal distance from previous prime (7369) and next prime (7393).

It can be written as a sum of positive squares in only one way, i.e., 4356 + 3025 = 66^2 + 55^2 .

It is not a de Polignac number, because 7381 - 25 = 7349 is a prime.

It is a super-2 number, since 2×73812 = 108958322, which contains 22 as substring.

It is a Duffinian number.

7381 is an undulating number in base 3.

7381 is a nontrivial repdigit in base 9.

It is a plaindrome in base 9 and base 13.

It is a nialpdrome in base 9 and base 12.

It is a zygodrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7321) by changing a digit.

It is a nontrivial repunit in base 9.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 91 + ... + 151.

27381 is an apocalyptic number.

7381 is the 121-st triangular number and also the 61-st hexagonal number.

7381 is the 41-st centered nonagonal number.

It is an amenable number.

7381 is a deficient number, since it is larger than the sum of its proper divisors (865).

7381 is a wasteful number, since it uses less digits than its factorization.

7381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83 (or 72 counting only the distinct ones).

The product of its digits is 168, while the sum is 19.

The square root of 7381 is about 85.9127464350. The cubic root of 7381 is about 19.4702592877.

The spelling of 7381 in words is "seven thousand, three hundred eighty-one".

Divisors: 1 11 61 121 671 7381