20904420 has 24 divisors (see below), whose sum is σ = 58532544. Its totient is φ = 5574496.

The previous prime is 20904413. The next prime is 20904421. The reversal of 20904420 is 2440902.

It is not an unprimeable number, because it can be changed into a prime (20904421) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 174144 + ... + 174263.

It is an arithmetic number, because the mean of its divisors is an integer number (2438856).

Almost surely, 2^20904420 is an apocalyptic number.

20904420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20904420 is an abundant number, since it is smaller than the sum of its proper divisors (37628124).

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

20904420 is a wasteful number, since it uses less digits than its factorization.

20904420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 348419 (or 348417 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 20904420 is about 4572.1351686056. The cubic root of 20904420 is about 275.4732127890.

The spelling of 20904420 in words is "twenty million, nine hundred four thousand, four hundred twenty".