20287404 has 36 divisors (see below), whose sum is σ = 51420096. Its totient is φ = 6744288.

The previous prime is 20287391. The next prime is 20287411. The reversal of 20287404 is 40478202.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×20287404² = 823157522118432, which contains 22 as substring.

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, 23077 + ... + 23939.

It is an arithmetic number, because the mean of its divisors is an integer number (1428336).

Almost surely, 2^20287404 is an apocalyptic number.

It is an amenable number.

20287404 is an abundant number, since it is smaller than the sum of its proper divisors (31132692).

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

20287404 is a wasteful number, since it uses less digits than its factorization.

20287404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1526 (or 1521 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 27.

The square root of 20287404 is about 4504.1540826220. The cubic root of 20287404 is about 272.7358068845.

The spelling of 20287404 in words is "twenty million, two hundred eighty-seven thousand, four hundred four".