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7961 = 19419
BaseRepresentation
bin1111100011001
3101220212
41330121
5223321
6100505
732132
oct17431
911825
107961
115a88
124735
133815
142c89
15255b
hex1f19

7961 has 4 divisors (see below), whose sum is σ = 8400. Its totient is φ = 7524.

The previous prime is 7951. The next prime is 7963. The reversal of 7961 is 1697.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a de Polignac number, because none of the positive numbers 2k-7961 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (7963) 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, 191 + ... + 228.

It is an arithmetic number, because the mean of its divisors is an integer number (2100).

27961 is an apocalyptic number.

It is an amenable number.

7961 is a deficient number, since it is larger than the sum of its proper divisors (439).

7961 is a wasteful number, since it uses less digits than its factorization.

7961 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 378, while the sum is 23.

The square root of 7961 is about 89.2244361148. The cubic root of 7961 is about 19.9674470440.

It can be divided in two parts, 796 and 1, that added together give a palindrome (797).

The spelling of 7961 in words is "seven thousand, nine hundred sixty-one".

Divisors: 1 19 419 7961