31458139 has 4 divisors (see below), whose sum is σ = 31544224. Its totient is φ = 31372056.

The previous prime is 31458131. The next prime is 31458169. The reversal of 31458139 is 93185413.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93185413 = 2113 ⋅44101.

It is a cyclic number.

It is not a de Polignac number, because 31458139 - 2³ = 31458131 is a prime.

It is a super-2 number, since 2×31458139² = 1979229018686642, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31458131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42492 + ... + 43225.

It is an arithmetic number, because the mean of its divisors is an integer number (7886056).

Almost surely, 2^31458139 is an apocalyptic number.

31458139 is a deficient number, since it is larger than the sum of its proper divisors (86085).

31458139 is an equidigital number, since it uses as much as digits as its factorization.

31458139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86084.

The product of its digits is 12960, while the sum is 34.

The square root of 31458139 is about 5608.7555660770. The cubic root of 31458139 is about 315.6780188553.

The spelling of 31458139 in words is "thirty-one million, four hundred fifty-eight thousand, one hundred thirty-nine".