21023203131 has 32 divisors (see below), whose sum is σ = 36822259200. Its totient is φ = 11599005600.

The previous prime is 21023203109. The next prime is 21023203139. The reversal of 21023203131 is 13130232012.

21023203131 is a `hidden beast` number, since 210 + 2 + 320 + 3 + 131 = 666.

It is not a de Polignac number, because 21023203131 - 2⁹ = 21023202619 is a prime.

It is a super-2 number, since 2×21023203131² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21023203139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1912345 + ... + 1923306.

It is an arithmetic number, because the mean of its divisors is an integer number (1150695600).

Almost surely, 2^21023203131 is an apocalyptic number.

21023203131 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21023203131 is a deficient number, since it is larger than the sum of its proper divisors (15799056069).

21023203131 is a wasteful number, since it uses less digits than its factorization.

21023203131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3835696 (or 3835690 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 21023203131 its reverse (13130232012), we get a palindrome (34153435143).

The spelling of 21023203131 in words is "twenty-one billion, twenty-three million, two hundred three thousand, one hundred thirty-one".