1921408900 has 36 divisors (see below), whose sum is σ = 4171678308. Its totient is φ = 768154240.

The previous prime is 1921408897. The next prime is 1921408913. The reversal of 1921408900 is 98041291.

It can be written as a sum of positive squares in 6 ways, for example, as 2268036 + 1919140864 = 1506^2 + 43808^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 243822 + ... + 251578.

It is an arithmetic number, because the mean of its divisors is an integer number (115879953).

Almost surely, 2^1921408900 is an apocalyptic number.

1921408900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1921408900 is an abundant number, since it is smaller than the sum of its proper divisors (2250269408).

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

1921408900 is a wasteful number, since it uses less digits than its factorization.

1921408900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10248 (or 10241 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 1921408900 is about 43833.8784503493. The cubic root of 1921408900 is about 1243.1969405417.

The spelling of 1921408900 in words is "one billion, nine hundred twenty-one million, four hundred eight thousand, nine hundred".