31112213221021 has 2 divisors, whose sum is σ = 31112213221022. Its totient is φ = 31112213221020.

The previous prime is 31112213221003. The next prime is 31112213221027. The reversal of 31112213221021 is 12012231221113.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24733613424100 + 6378599796921 = 4973290^2 + 2525589^2 .

It is a cyclic number.

It is not a de Polignac number, because 31112213221021 - 2⁵ = 31112213220989 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31112213220983 and 31112213221001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31112213221027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15556106610510 + 15556106610511.

It is an arithmetic number, because the mean of its divisors is an integer number (15556106610511).

Almost surely, 2^{31112213221021} is an apocalyptic number.

It is an amenable number.

31112213221021 is a deficient number, since it is larger than the sum of its proper divisors (1).

31112213221021 is an equidigital number, since it uses as much as digits as its factorization.

31112213221021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 22.

Adding to 31112213221021 its reverse (12012231221113), we get a palindrome (43124444442134).

The spelling of 31112213221021 in words is "thirty-one trillion, one hundred twelve billion, two hundred thirteen million, two hundred twenty-one thousand, twenty-one".