31310201221 has 16 divisors (see below), whose sum is σ = 35131719168. Its totient is φ = 27707976000.

The previous prime is 31310201203. The next prime is 31310201257. The reversal of 31310201221 is 12210201313.

It is a cyclic number.

It is not a de Polignac number, because 31310201221 - 2⁹ = 31310200709 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31310201195 and 31310201204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31310201201) 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 15 ways as a sum of consecutive naturals, for example, 319930 + ... + 406171.

It is an arithmetic number, because the mean of its divisors is an integer number (2195732448).

Almost surely, 2^31310201221 is an apocalyptic number.

31310201221 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

31310201221 is a deficient number, since it is larger than the sum of its proper divisors (3821517947).

31310201221 is a wasteful number, since it uses less digits than its factorization.

31310201221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 726252.

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

Adding to 31310201221 its reverse (12210201313), we get a palindrome (43520402534).

The spelling of 31310201221 in words is "thirty-one billion, three hundred ten million, two hundred one thousand, two hundred twenty-one".