20311013 has 4 divisors (see below), whose sum is σ = 20555808. Its totient is φ = 20066220.

The previous prime is 20310973. The next prime is 20311043. The reversal of 20311013 is 31011302.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20311013 - 2¹⁸ = 20048869 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20310985 and 20311003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20311043) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122273 + ... + 122438.

It is an arithmetic number, because the mean of its divisors is an integer number (5138952).

Almost surely, 2^20311013 is an apocalyptic number.

It is an amenable number.

20311013 is a deficient number, since it is larger than the sum of its proper divisors (244795).

20311013 is an equidigital number, since it uses as much as digits as its factorization.

20311013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 244794.

The product of its (nonzero) digits is 18, while the sum is 11.

The square root of 20311013 is about 4506.7741234724. The cubic root of 20311013 is about 272.8415625465.

Adding to 20311013 its reverse (31011302), we get a palindrome (51322315).

The spelling of 20311013 in words is "twenty million, three hundred eleven thousand, thirteen".