31213133233 has 2 divisors, whose sum is σ = 31213133234. Its totient is φ = 31213133232.

The previous prime is 31213133221. The next prime is 31213133243. The reversal of 31213133233 is 33233131213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16478086689 + 14735046544 = 128367^2 + 121388^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31213133233 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31213133198 and 31213133207.

It is not a weakly prime, because it can be changed into another prime (31213133243) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15606566616 + 15606566617.

It is an arithmetic number, because the mean of its divisors is an integer number (15606566617).

Almost surely, 2^31213133233 is an apocalyptic number.

It is an amenable number.

31213133233 is a deficient number, since it is larger than the sum of its proper divisors (1).

31213133233 is an equidigital number, since it uses as much as digits as its factorization.

31213133233 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2916, while the sum is 25.

Adding to 31213133233 its reverse (33233131213), we get a palindrome (64446264446).

The spelling of 31213133233 in words is "thirty-one billion, two hundred thirteen million, one hundred thirty-three thousand, two hundred thirty-three".