21313231131 has 16 divisors (see below), whose sum is σ = 28499305248. Its totient is φ = 14168044800.

The previous prime is 21313231103. The next prime is 21313231157. The reversal of 21313231131 is 13113231312.

It is a happy number.

It is not a de Polignac number, because 21313231131 - 2⁵ = 21313231099 is a prime.

It is a super-2 number, since 2×21313231131² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21313231098 and 21313231107.

It is not an unprimeable number, because it can be changed into a prime (21313231531) 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 15 ways as a sum of consecutive naturals, for example, 1715815 + ... + 1728191.

It is an arithmetic number, because the mean of its divisors is an integer number (1781206578).

Almost surely, 2^21313231131 is an apocalyptic number.

21313231131 is a deficient number, since it is larger than the sum of its proper divisors (7186074117).

21313231131 is a wasteful number, since it uses less digits than its factorization.

21313231131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13982.

The product of its digits is 324, while the sum is 21.

Adding to 21313231131 its reverse (13113231312), we get a palindrome (34426462443).

The spelling of 21313231131 in words is "twenty-one billion, three hundred thirteen million, two hundred thirty-one thousand, one hundred thirty-one".