21655505675 has 96 divisors (see below), whose sum is σ = 31112294400. Its totient is φ = 14852597760.

The previous prime is 21655505639. The next prime is 21655505689. The reversal of 21655505675 is 57650555612.

It is not a de Polignac number, because 21655505675 - 2¹⁶ = 21655440139 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 22394042 + ... + 22395008.

It is an arithmetic number, because the mean of its divisors is an integer number (324086400).

Almost surely, 2^21655505675 is an apocalyptic number.

21655505675 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21655505675 is a deficient number, since it is larger than the sum of its proper divisors (9456788725).

21655505675 is a wasteful number, since it uses less digits than its factorization.

21655505675 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1125 (or 1120 counting only the distinct ones).

The product of its (nonzero) digits is 1575000, while the sum is 47.

The spelling of 21655505675 in words is "twenty-one billion, six hundred fifty-five million, five hundred five thousand, six hundred seventy-five".