15956 has 6 divisors (see below), whose sum is σ = 27930. Its totient is φ = 7976.

The previous prime is 15937. The next prime is 15959. The reversal of 15956 is 65951.

It can be written as a sum of positive squares in only one way, i.e., 13456 + 2500 = 116^2 + 50^2 .

It is a plaindrome in base 9.

It is a nialpdrome in base 4.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 15956.

It is not an unprimeable number, because it can be changed into a prime (15959) by changing a digit.

15956 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1991 + ... + 1998.

It is an arithmetic number, because the mean of its divisors is an integer number (4655).

2¹⁵⁹⁵⁶ is an apocalyptic number.

It is an amenable number.

15956 is a deficient number, since it is larger than the sum of its proper divisors (11974).

15956 is a wasteful number, since it uses less digits than its factorization.

15956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3993 (or 3991 counting only the distinct ones).

The product of its digits is 1350, while the sum is 26.

The square root of 15956 is about 126.3170613971. The cubic root of 15956 is about 25.1753012392.

The spelling of 15956 in words is "fifteen thousand, nine hundred fifty-six".