20456904 has 64 divisors (see below), whose sum is σ = 55540800. Its totient is φ = 6241536.

The previous prime is 20456879. The next prime is 20456941. The reversal of 20456904 is 40965402.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53787 + ... + 54165.

It is an arithmetic number, because the mean of its divisors is an integer number (867825).

Almost surely, 2^20456904 is an apocalyptic number.

20456904 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20456904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27770400).

20456904 is an abundant number, since it is smaller than the sum of its proper divisors (35083896).

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

20456904 is a wasteful number, since it uses less digits than its factorization.

20456904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 574 (or 570 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 20456904 is about 4522.9309081612. The cubic root of 20456904 is about 273.4932648540.

The spelling of 20456904 in words is "twenty million, four hundred fifty-six thousand, nine hundred four".