31131213101 has 4 divisors (see below), whose sum is σ = 31131986304. Its totient is φ = 31130439900.

The previous prime is 31131213073. The next prime is 31131213107. The reversal of 31131213101 is 10131213113.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 31131213101 - 2²⁶ = 31064104237 is a prime.

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 31131213101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31131213107) 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, 322685 + ... + 407906.

It is an arithmetic number, because the mean of its divisors is an integer number (7782996576).

Almost surely, 2^31131213101 is an apocalyptic number.

It is an amenable number.

31131213101 is a deficient number, since it is larger than the sum of its proper divisors (773203).

31131213101 is an equidigital number, since it uses as much as digits as its factorization.

31131213101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 773202.

The product of its (nonzero) digits is 54, while the sum is 17.

Adding to 31131213101 its reverse (10131213113), we get a palindrome (41262426214).

The spelling of 31131213101 in words is "thirty-one billion, one hundred thirty-one million, two hundred thirteen thousand, one hundred one".