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7157 = 17421
BaseRepresentation
bin1101111110101
3100211002
41233311
5212112
653045
726603
oct15765
910732
107157
115417
124185
133347
142873
1521c2
hex1bf5

7157 has 4 divisors (see below), whose sum is σ = 7596. Its totient is φ = 6720.

The previous prime is 7151. The next prime is 7159. The reversal of 7157 is 7517.

It can be divided in two parts, 715 and 7, that multiplied together give a palindrome (5005).

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2116 + 5041 = 46^2 + 71^2 .

It is a cyclic number.

It is not a de Polignac number, because 7157 - 210 = 6133 is a prime.

It is a Duffinian number.

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7151) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 194 + ... + 227.

It is an arithmetic number, because the mean of its divisors is an integer number (1899).

27157 is an apocalyptic number.

It is an amenable number.

7157 is a deficient number, since it is larger than the sum of its proper divisors (439).

7157 is a wasteful number, since it uses less digits than its factorization.

7157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438.

The product of its digits is 245, while the sum is 20.

The square root of 7157 is about 84.5990543682. The cubic root of 7157 is about 19.2712701305.

The spelling of 7157 in words is "seven thousand, one hundred fifty-seven".

Divisors: 1 17 421 7157