31387679 has 2 divisors, whose sum is σ = 31387680. Its totient is φ = 31387678.

The previous prime is 31387649. The next prime is 31387693. The reversal of 31387679 is 97678313.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 31387679 - 2²⁰ = 30339103 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31387619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15693839 + 15693840.

It is an arithmetic number, because the mean of its divisors is an integer number (15693840).

Almost surely, 2^31387679 is an apocalyptic number.

31387679 is a deficient number, since it is larger than the sum of its proper divisors (1).

31387679 is an equidigital number, since it uses as much as digits as its factorization.

31387679 is an evil number, because the sum of its binary digits is even.

The product of its digits is 190512, while the sum is 44.

The square root of 31387679 is about 5602.4707942121. The cubic root of 31387679 is about 315.4421572627.

The spelling of 31387679 in words is "thirty-one million, three hundred eighty-seven thousand, six hundred seventy-nine".