31504221979 has 2 divisors, whose sum is σ = 31504221980. Its totient is φ = 31504221978.

The previous prime is 31504221977. The next prime is 31504222063. The reversal of 31504221979 is 97912240513.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31504221979 - 2¹ = 31504221977 is a prime.

It is a super-3 number, since 3×31504221979³ (a number of 32 digits) contains 333 as substring.

Together with 31504221977, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31504221977) 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 as a sum of consecutive naturals, namely, 15752110989 + 15752110990.

It is an arithmetic number, because the mean of its divisors is an integer number (15752110990).

Almost surely, 2^31504221979 is an apocalyptic number.

31504221979 is a deficient number, since it is larger than the sum of its proper divisors (1).

31504221979 is an equidigital number, since it uses as much as digits as its factorization.

31504221979 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 136080, while the sum is 43.

The spelling of 31504221979 in words is "thirty-one billion, five hundred four million, two hundred twenty-one thousand, nine hundred seventy-nine".