20819538 has 32 divisors (see below), whose sum is σ = 47761920. Its totient is φ = 6715440.

The previous prime is 20819521. The next prime is 20819563. The reversal of 20819538 is 83591802.

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, 4545 + ... + 7892.

It is an arithmetic number, because the mean of its divisors is an integer number (1492560).

Almost surely, 2^20819538 is an apocalyptic number.

20819538 is an abundant number, since it is smaller than the sum of its proper divisors (26942382).

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

20819538 is a wasteful number, since it uses less digits than its factorization.

20819538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12479 (or 12473 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 20819538 is about 4562.8431925719. The cubic root of 20819538 is about 275.0998557478.

The spelling of 20819538 in words is "twenty million, eight hundred nineteen thousand, five hundred thirty-eight".