31506563544561 has 48 divisors (see below), whose sum is σ = 52792638412800. Its totient is φ = 17733182585184.

The previous prime is 31506563544419. The next prime is 31506563544563. The reversal of 31506563544561 is 16544536560513.

31506563544561 is a `hidden beast` number, since 3 + 1 + 5 + 0 + 6 + 5 + 6 + 35 + 44 + 561 = 666.

It is not a de Polignac number, because 31506563544561 - 2¹³ = 31506563536369 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31506563544498 and 31506563544507.

It is not an unprimeable number, because it can be changed into a prime (31506563544563) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 40469470 + ... + 41240648.

It is an arithmetic number, because the mean of its divisors is an integer number (1099846633600).

Almost surely, 2^{31506563544561} is an apocalyptic number.

It is an amenable number.

31506563544561 is a deficient number, since it is larger than the sum of its proper divisors (21286074868239).

31506563544561 is a wasteful number, since it uses less digits than its factorization.

31506563544561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 780938 (or 780935 counting only the distinct ones).

The product of its (nonzero) digits is 19440000, while the sum is 54.

The spelling of 31506563544561 in words is "thirty-one trillion, five hundred six billion, five hundred sixty-three million, five hundred forty-four thousand, five hundred sixty-one".