12817639 has 2 divisors, whose sum is σ = 12817640. Its totient is φ = 12817638.

The previous prime is 12817631. The next prime is 12817657. The reversal of 12817639 is 93671821.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12817639 - 2³ = 12817631 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12817598 and 12817607.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12817631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6408819 + 6408820.

It is an arithmetic number, because the mean of its divisors is an integer number (6408820).

Almost surely, 2^12817639 is an apocalyptic number.

12817639 is a deficient number, since it is larger than the sum of its proper divisors (1).

12817639 is an equidigital number, since it uses as much as digits as its factorization.

12817639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18144, while the sum is 37.

The square root of 12817639 is about 3580.1730405108. The cubic root of 12817639 is about 234.0288212972.

It can be divided in two parts, 12817 and 639, that added together give a square (13456 = 116²).

The spelling of 12817639 in words is "twelve million, eight hundred seventeen thousand, six hundred thirty-nine".