1890221904 has 30 divisors (see below), whose sum is σ = 5289996426. Its totient is φ = 630073920.

The previous prime is 1890221873. The next prime is 1890221911. The reversal of 1890221904 is 4091220981.

1890221904 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 1830128400 + 60093504 = 42780^2 + 7752^2 .

It is a super-2 number, since 2×1890221904² = 7145877692722770432, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6563127 + ... + 6563414.

Almost surely, 2^1890221904 is an apocalyptic number.

It is an amenable number.

1890221904 is an abundant number, since it is smaller than the sum of its proper divisors (3399774522).

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

1890221904 is a wasteful number, since it uses less digits than its factorization.

1890221904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13126555 (or 13126546 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The square root of 1890221904 is about 43476.6823021260. The cubic root of 1890221904 is about 1236.4339758634.

The spelling of 1890221904 in words is "one billion, eight hundred ninety million, two hundred twenty-one thousand, nine hundred four".