31321211989 has 2 divisors, whose sum is σ = 31321211990. Its totient is φ = 31321211988.

The previous prime is 31321211983. The next prime is 31321212037. The reversal of 31321211989 is 98911212313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19539846225 + 11781365764 = 139785^2 + 108542^2 .

It is a cyclic number.

It is not a de Polignac number, because 31321211989 - 2¹⁵ = 31321179221 is a prime.

It is a super-2 number, since 2×31321211989² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31321211983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15660605994 + 15660605995.

It is an arithmetic number, because the mean of its divisors is an integer number (15660605995).

Almost surely, 2^31321211989 is an apocalyptic number.

It is an amenable number.

31321211989 is a deficient number, since it is larger than the sum of its proper divisors (1).

31321211989 is an equidigital number, since it uses as much as digits as its factorization.

31321211989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23328, while the sum is 40.

It can be divided in two parts, 3132 and 1211989, that added together give a palindrome (1215121).

The spelling of 31321211989 in words is "thirty-one billion, three hundred twenty-one million, two hundred eleven thousand, nine hundred eighty-nine".