31056561 has 8 divisors (see below), whose sum is σ = 46009760. Its totient is φ = 20704356.

The previous prime is 31056547. The next prime is 31056611. The reversal of 31056561 is 16565013.

It is a happy number.

31056561 is a `hidden beast` number, since 3 + 1 + 0 + 5 + 656 + 1 = 666.

It is not a de Polignac number, because 31056561 - 2⁶ = 31056497 is a prime.

It is a super-2 number, since 2×31056561² = 1929019962293442, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 1150243 = 31056561 / (3 + 1 + 0 + 5 + 6 + 5 + 6 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31056511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 575095 + ... + 575148.

It is an arithmetic number, because the mean of its divisors is an integer number (5751220).

Almost surely, 2^31056561 is an apocalyptic number.

It is an amenable number.

31056561 is a deficient number, since it is larger than the sum of its proper divisors (14953199).

31056561 is a wasteful number, since it uses less digits than its factorization.

31056561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1150252 (or 1150246 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 27.

The square root of 31056561 is about 5572.8413758154. The cubic root of 31056561 is about 314.3290025282.

The spelling of 31056561 in words is "thirty-one million, fifty-six thousand, five hundred sixty-one".