31201310221 has 4 divisors (see below), whose sum is σ = 32277217500. Its totient is φ = 30125402944.

The previous prime is 31201310207. The next prime is 31201310233. The reversal of 31201310221 is 12201310213.

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 10842015625 + 20359294596 = 104125^2 + 142686^2 .

It is a cyclic number.

It is not a de Polignac number, because 31201310221 - 2²¹ = 31199213069 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31201310195 and 31201310204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31201310201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 537953596 + ... + 537953653.

It is an arithmetic number, because the mean of its divisors is an integer number (8069304375).

Almost surely, 2^31201310221 is an apocalyptic number.

It is an amenable number.

31201310221 is a deficient number, since it is larger than the sum of its proper divisors (1075907279).

31201310221 is a wasteful number, since it uses less digits than its factorization.

31201310221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1075907278.

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

Adding to 31201310221 its reverse (12201310213), we get a palindrome (43402620434).

The spelling of 31201310221 in words is "thirty-one billion, two hundred one million, three hundred ten thousand, two hundred twenty-one".