31011113221 has 16 divisors (see below), whose sum is σ = 34954149888. Its totient is φ = 27257079600.

The previous prime is 31011113213. The next prime is 31011113249. The reversal of 31011113221 is 12231111013.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 31011113221 - 2³ = 31011113213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31011113195 and 31011113204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31011114221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 328836 + ... + 412498.

It is an arithmetic number, because the mean of its divisors is an integer number (2184634368).

Almost surely, 2^31011113221 is an apocalyptic number.

31011113221 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

31011113221 is a deficient number, since it is larger than the sum of its proper divisors (3943036667).

31011113221 is a wasteful number, since it uses less digits than its factorization.

31011113221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84792.

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 31011113221 its reverse (12231111013), we get a palindrome (43242224234).

The spelling of 31011113221 in words is "thirty-one billion, eleven million, one hundred thirteen thousand, two hundred twenty-one".