31112421997 has 2 divisors, whose sum is σ = 31112421998. Its totient is φ = 31112421996.

The previous prime is 31112421979. The next prime is 31112422037. The reversal of 31112421997 is 79912421113.

Together with previous prime (31112421979) it forms an Ormiston pair, because they use the same digits, order apart.

It is an a-pointer prime, because the next prime (31112422037) can be obtained adding 31112421997 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15862394916 + 15250027081 = 125946^2 + 123491^2 .

It is a cyclic number.

It is not a de Polignac number, because 31112421997 - 2³¹ = 28964938349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31112425997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15556210998 + 15556210999.

It is an arithmetic number, because the mean of its divisors is an integer number (15556210999).

Almost surely, 2^31112421997 is an apocalyptic number.

It is an amenable number.

31112421997 is a deficient number, since it is larger than the sum of its proper divisors (1).

31112421997 is an equidigital number, since it uses as much as digits as its factorization.

31112421997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27216, while the sum is 40.

The spelling of 31112421997 in words is "thirty-one billion, one hundred twelve million, four hundred twenty-one thousand, nine hundred ninety-seven".