921811212100 has 81 divisors (see below), whose sum is σ = 2032049652087. Its totient is φ = 362967665280.

The previous prime is 921811212089. The next prime is 921811212187. The reversal of 921811212100 is 1212118129.

The square root of 921811212100 is 960110.

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 42972460804 + 878838751296 = 207298^2 + 937464^2 .

It is a Duffinian 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 26 ways as a sum of consecutive naturals, for example, 643272984 + ... + 643274416.

Almost surely, 2^921811212100 is an apocalyptic number.

921811212100 is the 960110-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 921811212100

921811212100 is an abundant number, since it is smaller than the sum of its proper divisors (1110238439987).

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

921811212100 is an equidigital number, since it uses as much as digits as its factorization.

921811212100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3014 (or 1507 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 28.

Multiplying 921811212100 by its product of nonzero digits (576), we get a square (530963258169600 = 23042640²).

The spelling of 921811212100 in words is "nine hundred twenty-one billion, eight hundred eleven million, two hundred twelve thousand, one hundred".