312139 has 4 divisors (see below), whose sum is σ = 322240. Its totient is φ = 302040.

The previous prime is 312121. The next prime is 312161. The reversal of 312139 is 931213.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 312139 - 2⁵ = 312107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (312199) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5004 + ... + 5065.

It is an arithmetic number, because the mean of its divisors is an integer number (80560).

2³¹²¹³⁹ is an apocalyptic number.

312139 is a deficient number, since it is larger than the sum of its proper divisors (10101).

312139 is a wasteful number, since it uses less digits than its factorization.

312139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10100.

The product of its digits is 162, while the sum is 19.

The square root of 312139 is about 558.6940128550. The cubic root of 312139 is about 67.8342995527.

It can be divided in two parts, 3121 and 39, that added together give a triangular number (3160 = T₇₉).

The spelling of 312139 in words is "three hundred twelve thousand, one hundred thirty-nine".