21610656117 has 16 divisors (see below), whose sum is σ = 32106497280. Its totient is φ = 14366284416.

The previous prime is 21610656103. The next prime is 21610656127. The reversal of 21610656117 is 71165601612.

It is a happy number.

21610656117 is a `hidden beast` number, since 21 + 6 + 10 + 6 + 5 + 611 + 7 = 666.

It is not a de Polignac number, because 21610656117 - 2¹⁰ = 21610655093 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21610656127) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1124173 + ... + 1143234.

It is an arithmetic number, because the mean of its divisors is an integer number (2006656080).

Almost surely, 2^21610656117 is an apocalyptic number.

21610656117 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

21610656117 is a deficient number, since it is larger than the sum of its proper divisors (10495841163).

21610656117 is a wasteful number, since it uses less digits than its factorization.

21610656117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2267769 (or 2267763 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

The spelling of 21610656117 in words is "twenty-one billion, six hundred ten million, six hundred fifty-six thousand, one hundred seventeen".