31279387 has 2 divisors, whose sum is σ = 31279388. Its totient is φ = 31279386.

The previous prime is 31279373. The next prime is 31279411. The reversal of 31279387 is 78397213.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31279387 - 2¹¹ = 31277339 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (31279307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15639693 + 15639694.

It is an arithmetic number, because the mean of its divisors is an integer number (15639694).

Almost surely, 2^31279387 is an apocalyptic number.

31279387 is a deficient number, since it is larger than the sum of its proper divisors (1).

31279387 is an equidigital number, since it uses as much as digits as its factorization.

31279387 is an evil number, because the sum of its binary digits is even.

The product of its digits is 63504, while the sum is 40.

The square root of 31279387 is about 5592.7977792872. The cubic root of 31279387 is about 315.0789656736.

The spelling of 31279387 in words is "thirty-one million, two hundred seventy-nine thousand, three hundred eighty-seven".