20312131 has 16 divisors (see below), whose sum is σ = 23970816. Its totient is φ = 16851456.

The previous prime is 20312113. The next prime is 20312137. The reversal of 20312131 is 13121302.

It is a cyclic number.

It is not a de Polignac number, because 20312131 - 2⁹ = 20311619 is a prime.

It is a super-2 number, since 2×20312131² = 825165331522322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20312137) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34915 + ... + 35491.

It is an arithmetic number, because the mean of its divisors is an integer number (1498176).

Almost surely, 2^20312131 is an apocalyptic number.

20312131 is a deficient number, since it is larger than the sum of its proper divisors (3658685).

20312131 is a wasteful number, since it uses less digits than its factorization.

20312131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 738.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 20312131 is about 4506.8981572696. The cubic root of 20312131 is about 272.8465685544.

Adding to 20312131 its reverse (13121302), we get a palindrome (33433433).

The spelling of 20312131 in words is "twenty million, three hundred twelve thousand, one hundred thirty-one".