21758652817 has 24 divisors (see below), whose sum is σ = 24829801920. Its totient is φ = 19030149600.

The previous prime is 21758652803. The next prime is 21758652827. The reversal of 21758652817 is 71825685712.

It is not a de Polignac number, because 21758652817 - 2¹⁵ = 21758620049 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21758652827) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 982092 + ... + 1004002.

It is an arithmetic number, because the mean of its divisors is an integer number (1034575080).

Almost surely, 2^21758652817 is an apocalyptic number.

It is an amenable number.

21758652817 is a deficient number, since it is larger than the sum of its proper divisors (3071149103).

21758652817 is a wasteful number, since it uses less digits than its factorization.

21758652817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22245 (or 22234 counting only the distinct ones).

The product of its digits is 1881600, while the sum is 52.

The spelling of 21758652817 in words is "twenty-one billion, seven hundred fifty-eight million, six hundred fifty-two thousand, eight hundred seventeen".