20812188 has 12 divisors (see below), whose sum is σ = 48561800. Its totient is φ = 6937392.

The previous prime is 20812177. The next prime is 20812189. The reversal of 20812188 is 88121802.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20812189) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 867163 + ... + 867186.

Almost surely, 2^20812188 is an apocalyptic number.

It is an amenable number.

20812188 is an abundant number, since it is smaller than the sum of its proper divisors (27749612).

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

20812188 is a wasteful number, since it uses less digits than its factorization.

20812188 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1734356 (or 1734354 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 30.

The square root of 20812188 is about 4562.0377026062. The cubic root of 20812188 is about 275.0674787577.

The spelling of 20812188 in words is "twenty million, eight hundred twelve thousand, one hundred eighty-eight".