20518812 has 24 divisors (see below), whose sum is σ = 53197200. Its totient is φ = 6839568.

The previous prime is 20518811. The next prime is 20518853. The reversal of 20518812 is 21881502.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20518811) 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 7 ways as a sum of consecutive naturals, for example, 94887 + ... + 95102.

It is an arithmetic number, because the mean of its divisors is an integer number (2216550).

Almost surely, 2^20518812 is an apocalyptic number.

It is an amenable number.

20518812 is an abundant number, since it is smaller than the sum of its proper divisors (32678388).

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

20518812 is a wasteful number, since it uses less digits than its factorization.

20518812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 190002 (or 189994 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 27.

The square root of 20518812 is about 4529.7695305611. The cubic root of 20518812 is about 273.7688746603.

The spelling of 20518812 in words is "twenty million, five hundred eighteen thousand, eight hundred twelve".