20939858 has 8 divisors (see below), whose sum is σ = 31467852. Its totient is φ = 10450576.

The previous prime is 20939857. The next prime is 20939873. The reversal of 20939858 is 85893902.

It can be written as a sum of positive squares in 2 ways, for example, as 20857489 + 82369 = 4567^2 + 287^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (20939857) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8285 + ... + 10512.

Almost surely, 2^20939858 is an apocalyptic number.

20939858 is a deficient number, since it is larger than the sum of its proper divisors (10527994).

20939858 is a wasteful number, since it uses less digits than its factorization.

20939858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19356.

The product of its (nonzero) digits is 155520, while the sum is 44.

The square root of 20939858 is about 4576.0089597814. The cubic root of 20939858 is about 275.6287892727.

The spelling of 20939858 in words is "twenty million, nine hundred thirty-nine thousand, eight hundred fifty-eight".