21657475611 has 12 divisors (see below), whose sum is σ = 31288306192. Its totient is φ = 14435877456.

The previous prime is 21657475597. The next prime is 21657475613. The reversal of 21657475611 is 11657475612.

21657475611 is a `hidden beast` number, since 2 + 1 + 6 + 574 + 75 + 6 + 1 + 1 = 666.

It is not a de Polignac number, because 21657475611 - 2³⁰ = 20583733787 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21657475613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 146236 + ... + 254361.

Almost surely, 2^21657475611 is an apocalyptic number.

21657475611 is a deficient number, since it is larger than the sum of its proper divisors (9630830581).

21657475611 is a wasteful number, since it uses less digits than its factorization.

21657475611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 406610 (or 406607 counting only the distinct ones).

The product of its digits is 352800, while the sum is 45.

Subtracting from 21657475611 its reverse (11657475612), we obtain a palindrome (9999999999).

The spelling of 21657475611 in words is "twenty-one billion, six hundred fifty-seven million, four hundred seventy-five thousand, six hundred eleven".