31447721421 has 8 divisors (see below), whose sum is σ = 46589216960. Its totient is φ = 20965147596.

The previous prime is 31447721407. The next prime is 31447721441. The reversal of 31447721421 is 12412774413.

31447721421 is a `hidden beast` number, since 3 + 1 + 447 + 72 + 142 + 1 = 666.

It is not a de Polignac number, because 31447721421 - 2⁷ = 31447721293 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31447721441) 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 7 ways as a sum of consecutive naturals, for example, 582365185 + ... + 582365238.

It is an arithmetic number, because the mean of its divisors is an integer number (5823652120).

Almost surely, 2^31447721421 is an apocalyptic number.

It is an amenable number.

31447721421 is a deficient number, since it is larger than the sum of its proper divisors (15141495539).

31447721421 is a wasteful number, since it uses less digits than its factorization.

31447721421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1164730432 (or 1164730426 counting only the distinct ones).

The product of its digits is 37632, while the sum is 36.

The spelling of 31447721421 in words is "thirty-one billion, four hundred forty-seven million, seven hundred twenty-one thousand, four hundred twenty-one".