1308639 has 8 divisors (see below), whose sum is σ = 1750320. Its totient is φ = 869696.

The previous prime is 1308613. The next prime is 1308647. The reversal of 1308639 is 9368031.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1308639 - 2⁵ = 1308607 is a prime.

1308639 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1308649) 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 7 ways as a sum of consecutive naturals, for example, 1099 + ... + 1955.

It is an arithmetic number, because the mean of its divisors is an integer number (218790).

2^1308639 is an apocalyptic number.

1308639 is a deficient number, since it is larger than the sum of its proper divisors (441681).

1308639 is an equidigital number, since it uses as much as digits as its factorization.

1308639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1369.

The product of its (nonzero) digits is 3888, while the sum is 30.

The square root of 1308639 is about 1143.9576041095. The cubic root of 1308639 is about 109.3805122664.

The spelling of 1308639 in words is "one million, three hundred eight thousand, six hundred thirty-nine".