31211201231 has 4 divisors (see below), whose sum is σ = 35669944272. Its totient is φ = 26752458192.

The previous prime is 31211201191. The next prime is 31211201261. The reversal of 31211201231 is 13210211213.

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 31211201231 - 2⁶ = 31211201167 is a prime.

It is a super-2 number, since 2×31211201231² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31211201261) 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 3 ways as a sum of consecutive naturals, for example, 2229371510 + ... + 2229371523.

It is an arithmetic number, because the mean of its divisors is an integer number (8917486068).

Almost surely, 2^31211201231 is an apocalyptic number.

31211201231 is a deficient number, since it is larger than the sum of its proper divisors (4458743041).

31211201231 is an equidigital number, since it uses as much as digits as its factorization.

31211201231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4458743040.

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

Adding to 31211201231 its reverse (13210211213), we get a palindrome (44421412444).

The spelling of 31211201231 in words is "thirty-one billion, two hundred eleven million, two hundred one thousand, two hundred thirty-one".