21717136125 has 128 divisors (see below), whose sum is σ = 41928506880. Its totient is φ = 11080800000.

The previous prime is 21717136109. The next prime is 21717136171. The reversal of 21717136125 is 52163171712.

21717136125 is a `hidden beast` number, since 2 + 17 + 17 + 13 + 612 + 5 = 666.

It is not a de Polignac number, because 21717136125 - 2⁴ = 21717136109 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21717136125.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 7615950 + ... + 7618800.

It is an arithmetic number, because the mean of its divisors is an integer number (327566460).

Almost surely, 2^21717136125 is an apocalyptic number.

21717136125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21717136125 is a deficient number, since it is larger than the sum of its proper divisors (20211370755).

21717136125 is a wasteful number, since it uses less digits than its factorization.

21717136125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2973 (or 2957 counting only the distinct ones).

The product of its digits is 17640, while the sum is 36.

The spelling of 21717136125 in words is "twenty-one billion, seven hundred seventeen million, one hundred thirty-six thousand, one hundred twenty-five".