31604555664561 has 32 divisors (see below), whose sum is σ = 47485701181440. Its totient is φ = 18523690545600.

The previous prime is 31604555664523. The next prime is 31604555664569. The reversal of 31604555664561 is 16546655540613.

It is not a de Polignac number, because 31604555664561 - 2¹³ = 31604555656369 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31604555664569) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9094830 + ... + 12079943.

It is an arithmetic number, because the mean of its divisors is an integer number (1483928161920).

Almost surely, 2^{31604555664561} is an apocalyptic number.

31604555664561 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

31604555664561 is a deficient number, since it is larger than the sum of its proper divisors (15881145516879).

31604555664561 is a wasteful number, since it uses less digits than its factorization.

31604555664561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21176277.

The product of its (nonzero) digits is 38880000, while the sum is 57.

The spelling of 31604555664561 in words is "thirty-one trillion, six hundred four billion, five hundred fifty-five million, six hundred sixty-four thousand, five hundred sixty-one".