20858885 has 4 divisors (see below), whose sum is σ = 25030668. Its totient is φ = 16687104.

The previous prime is 20858879. The next prime is 20858897. The reversal of 20858885 is 58885802.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8797156 + 12061729 = 2966^2 + 3473^2 .

It is a cyclic number.

It is not a de Polignac number, because 20858885 - 2⁴ = 20858869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2085884 + ... + 2085893.

It is an arithmetic number, because the mean of its divisors is an integer number (6257667).

Almost surely, 2^20858885 is an apocalyptic number.

It is an amenable number.

20858885 is a deficient number, since it is larger than the sum of its proper divisors (4171783).

20858885 is an equidigital number, since it uses as much as digits as its factorization.

20858885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4171782.

The product of its (nonzero) digits is 204800, while the sum is 44.

The square root of 20858885 is about 4567.1528330022. The cubic root of 20858885 is about 275.2730511083.

The spelling of 20858885 in words is "twenty million, eight hundred fifty-eight thousand, eight hundred eighty-five".