20306872 has 8 divisors (see below), whose sum is σ = 38075400. Its totient is φ = 10153432.

The previous prime is 20306837. The next prime is 20306887. The reversal of 20306872 is 27860302.

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 20306872.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1269172 + ... + 1269187.

It is an arithmetic number, because the mean of its divisors is an integer number (4759425).

Almost surely, 2^20306872 is an apocalyptic number.

It is an amenable number.

20306872 is a deficient number, since it is larger than the sum of its proper divisors (17768528).

20306872 is a wasteful number, since it uses less digits than its factorization.

20306872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2538365 (or 2538361 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 20306872 is about 4506.3146805344. The cubic root of 20306872 is about 272.8230190154.

The spelling of 20306872 in words is "twenty million, three hundred six thousand, eight hundred seventy-two".