12508391 has 4 divisors (see below), whose sum is σ = 14295312. Its totient is φ = 10721472.

The previous prime is 12508373. The next prime is 12508409. The reversal of 12508391 is 19380521.

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

It is an interprime number because it is at equal distance from previous prime (12508373) and next prime (12508409).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12508391 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12508351) 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 in 3 ways as a sum of consecutive naturals, for example, 893450 + ... + 893463.

It is an arithmetic number, because the mean of its divisors is an integer number (3573828).

Almost surely, 2^12508391 is an apocalyptic number.

12508391 is a deficient number, since it is larger than the sum of its proper divisors (1786921).

12508391 is an equidigital number, since it uses as much as digits as its factorization.

12508391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1786920.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 12508391 is about 3536.7203734533. The cubic root of 12508391 is about 232.1313601610.

It can be divided in two parts, 12508 and 391, that multiplied together give a triangular number (4890628 = T₃₁₂₇).

The spelling of 12508391 in words is "twelve million, five hundred eight thousand, three hundred ninety-one".