20188805 has 16 divisors (see below), whose sum is σ = 29817984. Its totient is φ = 12778560.

The previous prime is 20188799. The next prime is 20188823. The reversal of 20188805 is 50888102.

It is not a de Polignac number, because 20188805 - 2¹² = 20184709 is a prime.

It is a congruent number.

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, 21731 + ... + 22640.

It is an arithmetic number, because the mean of its divisors is an integer number (1863624).

Almost surely, 2^20188805 is an apocalyptic number.

It is an amenable number.

20188805 is a deficient number, since it is larger than the sum of its proper divisors (9629179).

20188805 is a wasteful number, since it uses less digits than its factorization.

20188805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44396.

The product of its (nonzero) digits is 5120, while the sum is 32.

The square root of 20188805 is about 4493.1954108407. The cubic root of 20188805 is about 272.2932472054.

The spelling of 20188805 in words is "twenty million, one hundred eighty-eight thousand, eight hundred five".