21031120131 has 64 divisors (see below), whose sum is σ = 34051691520. Its totient is φ = 11290728960.

The previous prime is 21031120129. The next prime is 21031120133. The reversal of 21031120131 is 13102113012.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21031120129) and next prime (21031120133).

It is not a de Polignac number, because 21031120131 - 2¹ = 21031120129 is a prime.

It is a super-2 number, since 2×21031120131² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21031120131.

It is not an unprimeable number, because it can be changed into a prime (21031120133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7671421 + ... + 7674161.

It is an arithmetic number, because the mean of its divisors is an integer number (532057680).

Almost surely, 2^21031120131 is an apocalyptic number.

21031120131 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21031120131 is a deficient number, since it is larger than the sum of its proper divisors (13020571389).

21031120131 is a wasteful number, since it uses less digits than its factorization.

21031120131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3116.

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 21031120131 its reverse (13102113012), we get a palindrome (34133233143).

The spelling of 21031120131 in words is "twenty-one billion, thirty-one million, one hundred twenty thousand, one hundred thirty-one".