21610325817 has 12 divisors (see below), whose sum is σ = 31228279524. Its totient is φ = 14400715680.

The previous prime is 21610325767. The next prime is 21610325819. The reversal of 21610325817 is 71852301612.

21610325817 is a `hidden beast` number, since 2 + 1 + 610 + 3 + 25 + 8 + 17 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 16789939776 + 4820386041 = 129576^2 + 69429^2 .

It is not a de Polignac number, because 21610325817 - 2⁶ = 21610325753 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21610325819) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 491778 + ... + 533915.

It is an arithmetic number, because the mean of its divisors is an integer number (2602356627).

Almost surely, 2^21610325817 is an apocalyptic number.

It is an amenable number.

21610325817 is a deficient number, since it is larger than the sum of its proper divisors (9617953707).

21610325817 is a wasteful number, since it uses less digits than its factorization.

21610325817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1028040 (or 1028037 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The spelling of 21610325817 in words is "twenty-one billion, six hundred ten million, three hundred twenty-five thousand, eight hundred seventeen".