20310813 has 12 divisors (see below), whose sum is σ = 29437408. Its totient is φ = 13494600.

The previous prime is 20310803. The next prime is 20310833. The reversal of 20310813 is 31801302.

It is not a de Polignac number, because 20310813 - 2⁵ = 20310781 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20310803) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 913 + ... + 6438.

Almost surely, 2^20310813 is an apocalyptic number.

It is an amenable number.

20310813 is a deficient number, since it is larger than the sum of its proper divisors (9126595).

20310813 is a wasteful number, since it uses less digits than its factorization.

20310813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7664 (or 7661 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 20310813 is about 4506.7519345977. The cubic root of 20310813 is about 272.8406669980.

The spelling of 20310813 in words is "twenty million, three hundred ten thousand, eight hundred thirteen".