31133012021 has 2 divisors, whose sum is σ = 31133012022. Its totient is φ = 31133012020.

The previous prime is 31133011993. The next prime is 31133012063. The reversal of 31133012021 is 12021033113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15853579921 + 15279432100 = 125911^2 + 123610^2 .

It is an emirp because it is prime and its reverse (12021033113) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31133012021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31133012081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15566506010 + 15566506011.

It is an arithmetic number, because the mean of its divisors is an integer number (15566506011).

Almost surely, 2^31133012021 is an apocalyptic number.

It is an amenable number.

31133012021 is a deficient number, since it is larger than the sum of its proper divisors (1).

31133012021 is an equidigital number, since it uses as much as digits as its factorization.

31133012021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108, while the sum is 17.

Adding to 31133012021 its reverse (12021033113), we get a palindrome (43154045134).

The spelling of 31133012021 in words is "thirty-one billion, one hundred thirty-three million, twelve thousand, twenty-one".