21117055525 has 12 divisors (see below), whose sum is σ = 27563315200. Its totient is φ = 16004504880.

The previous prime is 21117055501. The next prime is 21117055549. The reversal of 21117055525 is 52555071112.

It is an interprime number because it is at equal distance from previous prime (21117055501) and next prime (21117055549).

It is not a de Polignac number, because 21117055525 - 2⁵ = 21117055493 is a prime.

It is a congruent number.

It is an unprimeable number.

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, 22228005 + ... + 22228954.

Almost surely, 2^21117055525 is an apocalyptic number.

21117055525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21117055525 is a deficient number, since it is larger than the sum of its proper divisors (6446259675).

21117055525 is a wasteful number, since it uses less digits than its factorization.

21117055525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44456988 (or 44456983 counting only the distinct ones).

The product of its (nonzero) digits is 17500, while the sum is 34.

The spelling of 21117055525 in words is "twenty-one billion, one hundred seventeen million, fifty-five thousand, five hundred twenty-five".