1231331304331 has 4 divisors (see below), whose sum is σ = 1231334782600. Its totient is φ = 1231327826064.

The previous prime is 1231331304221. The next prime is 1231331304403. The reversal of 1231331304331 is 1334031331321.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1231331304331 is a prime.

It is a super-2 number, since 2×1231331304331² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1231331304331.

It is not an unprimeable number, because it can be changed into a prime (1231331301331) 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, 1139121 + ... + 1939138.

It is an arithmetic number, because the mean of its divisors is an integer number (307833695650).

Almost surely, 2^{1231331304331} is an apocalyptic number.

1231331304331 is a deficient number, since it is larger than the sum of its proper divisors (3478269).

1231331304331 is an equidigital number, since it uses as much as digits as its factorization.

1231331304331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3478268.

The product of its (nonzero) digits is 5832, while the sum is 28.

Adding to 1231331304331 its reverse (1334031331321), we get a palindrome (2565362635652).

The spelling of 1231331304331 in words is "one trillion, two hundred thirty-one billion, three hundred thirty-one million, three hundred four thousand, three hundred thirty-one".