131231001021 has 8 divisors (see below), whose sum is σ = 174990339744. Its totient is φ = 87479498160.

The previous prime is 131231000993. The next prime is 131231001023. The reversal of 131231001021 is 120100132131.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 131231001021 - 2¹⁹ = 131230476733 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131231001023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1919775 + ... + 1986956.

It is an arithmetic number, because the mean of its divisors is an integer number (21873792468).

Almost surely, 2^131231001021 is an apocalyptic number.

It is an amenable number.

131231001021 is a deficient number, since it is larger than the sum of its proper divisors (43759338723).

131231001021 is a wasteful number, since it uses less digits than its factorization.

131231001021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3917931.

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

Adding to 131231001021 its reverse (120100132131), we get a palindrome (251331133152).

The spelling of 131231001021 in words is "one hundred thirty-one billion, two hundred thirty-one million, one thousand, twenty-one".