21817933309690 has 32 divisors (see below), whose sum is σ = 45236012027904. Its totient is φ = 7421533217280.

The previous prime is 21817933309687. The next prime is 21817933309717. The reversal of 21817933309690 is 9690333971812.

It is a super-2 number, since 2×21817933309690² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1227096471 + ... + 1227114250.

It is an arithmetic number, because the mean of its divisors is an integer number (1413625375872).

Almost surely, 2^{21817933309690} is an apocalyptic number.

21817933309690 is an abundant number, since it is smaller than the sum of its proper divisors (23418078718214).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21817933309690 is a wasteful number, since it uses less digits than its factorization.

21817933309690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2454210862.

The product of its (nonzero) digits is 13226976, while the sum is 61.

The spelling of 21817933309690 in words is "twenty-one trillion, eight hundred seventeen billion, nine hundred thirty-three million, three hundred nine thousand, six hundred ninety".