20902638 has 32 divisors (see below), whose sum is σ = 42923520. Its totient is φ = 6783680.

The previous prime is 20902633. The next prime is 20902667. The reversal of 20902638 is 83620902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20902633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48283 + ... + 48713.

It is an arithmetic number, because the mean of its divisors is an integer number (1341360).

Almost surely, 2^20902638 is an apocalyptic number.

20902638 is an abundant number, since it is smaller than the sum of its proper divisors (22020882).

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

20902638 is a wasteful number, since it uses less digits than its factorization.

20902638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 632.

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 20902638 is about 4571.9402883240. The cubic root of 20902638 is about 275.4653849833.

The spelling of 20902638 in words is "twenty million, nine hundred two thousand, six hundred thirty-eight".