31131104211211 has 4 divisors (see below), whose sum is σ = 31131122842872. Its totient is φ = 31131085579552.

The previous prime is 31131104211197. The next prime is 31131104211217. The reversal of 31131104211211 is 11211240113113.

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-31131104211211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31131104211217) 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, 6532285 + ... + 10243678.

It is an arithmetic number, because the mean of its divisors is an integer number (7782780710718).

Almost surely, 2^{31131104211211} is an apocalyptic number.

31131104211211 is a deficient number, since it is larger than the sum of its proper divisors (18631661).

31131104211211 is a wasteful number, since it uses less digits than its factorization.

31131104211211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18631660.

The product of its (nonzero) digits is 144, while the sum is 22.

Adding to 31131104211211 its reverse (11211240113113), we get a palindrome (42342344324324).

The spelling of 31131104211211 in words is "thirty-one trillion, one hundred thirty-one billion, one hundred four million, two hundred eleven thousand, two hundred eleven".