20904288 has 48 divisors (see below), whose sum is σ = 58106160. Its totient is φ = 6557696.

The previous prime is 20904283. The next prime is 20904293. The reversal of 20904288 is 88240902.

It is an interprime number because it is at equal distance from previous prime (20904283) and next prime (20904293).

It is a tau number, because it is divible by the number of its divisors (48).

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20904281) 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, 4773 + ... + 8036.

It is an arithmetic number, because the mean of its divisors is an integer number (1210545).

Almost surely, 2^20904288 is an apocalyptic number.

It is an amenable number.

20904288 is an abundant number, since it is smaller than the sum of its proper divisors (37201872).

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

20904288 is a wasteful number, since it uses less digits than its factorization.

20904288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12839 (or 12831 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 20904288 is about 4572.1207333140. The cubic root of 20904288 is about 275.4726329668.

The spelling of 20904288 in words is "twenty million, nine hundred four thousand, two hundred eighty-eight".