31213122001 has 4 divisors (see below), whose sum is σ = 31347084132. Its totient is φ = 31079159872.

The previous prime is 31213121987. The next prime is 31213122023. The reversal of 31213122001 is 10022131213.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10534969600 + 20678152401 = 102640^2 + 143799^2 .

It is a cyclic number.

It is not a de Polignac number, because 31213122001 - 2²⁷ = 31078904273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31213122071) 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 in 3 ways as a sum of consecutive naturals, for example, 66980716 + ... + 66981181.

It is an arithmetic number, because the mean of its divisors is an integer number (7836771033).

Almost surely, 2^31213122001 is an apocalyptic number.

It is an amenable number.

31213122001 is a deficient number, since it is larger than the sum of its proper divisors (133962131).

31213122001 is a wasteful number, since it uses less digits than its factorization.

31213122001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133962130.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 31213122001 its reverse (10022131213), we get a palindrome (41235253214).

The spelling of 31213122001 in words is "thirty-one billion, two hundred thirteen million, one hundred twenty-two thousand, one".