31402213021 has 2 divisors, whose sum is σ = 31402213022. Its totient is φ = 31402213020.

The previous prime is 31402213001. The next prime is 31402213033. The reversal of 31402213021 is 12031220413.

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., 29373160996 + 2029052025 = 171386^2 + 45045^2 .

It is a cyclic number.

It is not a de Polignac number, because 31402213021 - 2¹⁵ = 31402180253 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31402213021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31402213001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15701106510 + 15701106511.

It is an arithmetic number, because the mean of its divisors is an integer number (15701106511).

Almost surely, 2^31402213021 is an apocalyptic number.

It is an amenable number.

31402213021 is a deficient number, since it is larger than the sum of its proper divisors (1).

31402213021 is an equidigital number, since it uses as much as digits as its factorization.

31402213021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 31402213021 its reverse (12031220413), we get a palindrome (43433433434).

The spelling of 31402213021 in words is "thirty-one billion, four hundred two million, two hundred thirteen thousand, twenty-one".