109999018921 has 15 divisors (see below), whose sum is σ = 121042329415. Its totient is φ = 99962625400.

The previous prime is 109999018907. The next prime is 109999018933. The reversal of 109999018921 is 129810999901.

The square root of 109999018921 is 331661.

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

It can be written as a sum of positive squares in only one way, i.e., 32548128921 + 77450890000 = 180411^2 + 278300^2 .

It is not a de Polignac number, because 109999018921 - 2⁷ = 109999018793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (109999048921) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 40129611 + ... + 40132351.

Almost surely, 2^109999018921 is an apocalyptic number.

109999018921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

109999018921 is the 331661-st square number.

109999018921 is the 165831-st centered octagonal number.

It is an amenable number.

109999018921 is a deficient number, since it is larger than the sum of its proper divisors (11043310494).

109999018921 is an frugal number, since it uses more digits than its factorization.

109999018921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5526 (or 2752 counting only the distinct ones).

The product of its (nonzero) digits is 944784, while the sum is 58.

The spelling of 109999018921 in words is "one hundred nine billion, nine hundred ninety-nine million, eighteen thousand, nine hundred twenty-one".