31212002021 has 2 divisors, whose sum is σ = 31212002022. Its totient is φ = 31212002020.

The previous prime is 31212001987. The next prime is 31212002027. The reversal of 31212002021 is 12020021213.

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., 22167040996 + 9044961025 = 148886^2 + 95105^2 .

It is a cyclic number.

It is not a de Polignac number, because 31212002021 - 2³⁴ = 14032132837 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31212001987 and 31212002005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31212002027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15606001010 + 15606001011.

It is an arithmetic number, because the mean of its divisors is an integer number (15606001011).

Almost surely, 2^31212002021 is an apocalyptic number.

It is an amenable number.

31212002021 is a deficient number, since it is larger than the sum of its proper divisors (1).

31212002021 is an equidigital number, since it uses as much as digits as its factorization.

31212002021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 31212002021 its reverse (12020021213), we get a palindrome (43232023234).

The spelling of 31212002021 in words is "thirty-one billion, two hundred twelve million, two thousand, twenty-one".