20308806 has 40 divisors (see below), whose sum is σ = 52010640. Its totient is φ = 5802192.

The previous prime is 20308789. The next prime is 20308823. The reversal of 20308806 is 60880302.

It is an interprime number because it is at equal distance from previous prime (20308789) and next prime (20308823).

It is a super-2 number, since 2×20308806² = 824895202291272, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 20308806.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 7821 + ... + 10088.

It is an arithmetic number, because the mean of its divisors is an integer number (1300266).

Almost surely, 2^20308806 is an apocalyptic number.

20308806 is an abundant number, since it is smaller than the sum of its proper divisors (31701834).

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

20308806 is a wasteful number, since it uses less digits than its factorization.

20308806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17930 (or 17921 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 20308806 is about 4506.5292631914. The cubic root of 20308806 is about 272.8316798433.

The spelling of 20308806 in words is "twenty million, three hundred eight thousand, eight hundred six".