18931522975369 has 9 divisors (see below), whose sum is σ = 18951301668693. Its totient is φ = 18911764916352.

The previous prime is 18931522975327. The next prime is 18931522975381. The reversal of 18931522975369 is 96357922513981.

The square root of 18931522975369 is 4351037.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 13966701212025 + 4964821763344 = 3737205^2 + 2228188^2 .

It is a de Polignac number, because none of the positive numbers 2^k-18931522975369 is a prime.

It is a super-2 number, since 2×18931522975369² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18931522975298 and 18931522975307.

It is not an unprimeable number, because it can be changed into a prime (18931522975669) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5973972217 + ... + 5973975385.

Almost surely, 2^{18931522975369} is an apocalyptic number.

18931522975369 is the 4351037-th square number.

18931522975369 is the 2175519-th centered octagonal number.

It is an amenable number.

18931522975369 is a deficient number, since it is larger than the sum of its proper divisors (19778693324).

18931522975369 is an frugal number, since it uses more digits than its factorization.

18931522975369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9084 (or 4542 counting only the distinct ones).

The product of its digits is 220449600, while the sum is 70.

The spelling of 18931522975369 in words is "eighteen trillion, nine hundred thirty-one billion, five hundred twenty-two million, nine hundred seventy-five thousand, three hundred sixty-nine".