1231001220131 has 4 divisors (see below), whose sum is σ = 1251181568064. Its totient is φ = 1210820872200.

The previous prime is 1231001220103. The next prime is 1231001220133. The reversal of 1231001220131 is 1310221001321.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1231001220131 - 2¹⁸ = 1231000957987 is a prime.

It is a super-2 number, since 2×1231001220131² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1231001220133) 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, 10090173875 + ... + 10090173996.

It is an arithmetic number, because the mean of its divisors is an integer number (312795392016).

Almost surely, 2^{1231001220131} is an apocalyptic number.

1231001220131 is a deficient number, since it is larger than the sum of its proper divisors (20180347933).

1231001220131 is an equidigital number, since it uses as much as digits as its factorization.

1231001220131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20180347932.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 1231001220131 its reverse (1310221001321), we get a palindrome (2541222221452).

The spelling of 1231001220131 in words is "one trillion, two hundred thirty-one billion, one million, two hundred twenty thousand, one hundred thirty-one".