31311021213133 has 4 divisors (see below), whose sum is σ = 31311149465248. Its totient is φ = 31310892961020.

The previous prime is 31311021213089. The next prime is 31311021213187. The reversal of 31311021213133 is 33131212011313.

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 31311021213133 - 2¹³ = 31311021204941 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31311021213098 and 31311021213107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31311021214133) 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, 63759153 + ... + 64248358.

It is an arithmetic number, because the mean of its divisors is an integer number (7827787366312).

Almost surely, 2^{31311021213133} is an apocalyptic number.

It is an amenable number.

31311021213133 is a deficient number, since it is larger than the sum of its proper divisors (128252115).

31311021213133 is a wasteful number, since it uses less digits than its factorization.

31311021213133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128252114.

The product of its (nonzero) digits is 972, while the sum is 25.

Adding to 31311021213133 its reverse (33131212011313), we get a palindrome (64442233224446).

The spelling of 31311021213133 in words is "thirty-one trillion, three hundred eleven billion, twenty-one million, two hundred thirteen thousand, one hundred thirty-three".