31438387 has 2 divisors, whose sum is σ = 31438388. Its totient is φ = 31438386.

The previous prime is 31438373. The next prime is 31438397. The reversal of 31438387 is 78383413.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 31438387 - 2⁷ = 31438259 is a prime.

It is not a weakly prime, because it can be changed into another prime (31438357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15719193 + 15719194.

It is an arithmetic number, because the mean of its divisors is an integer number (15719194).

Almost surely, 2^31438387 is an apocalyptic number.

31438387 is a deficient number, since it is larger than the sum of its proper divisors (1).

31438387 is an equidigital number, since it uses as much as digits as its factorization.

31438387 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48384, while the sum is 37.

The square root of 31438387 is about 5606.9944711940. The cubic root of 31438387 is about 315.6119355047.

The spelling of 31438387 in words is "thirty-one million, four hundred thirty-eight thousand, three hundred eighty-seven".