308998639 has 4 divisors (see below), whose sum is σ = 314828856. Its totient is φ = 303168424.

The previous prime is 308998601. The next prime is 308998709. The reversal of 308998639 is 936899803.

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 308998639 - 2¹⁹ = 308474351 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 308998639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (308998139) 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, 2915029 + ... + 2915134.

It is an arithmetic number, because the mean of its divisors is an integer number (78707214).

Almost surely, 2^308998639 is an apocalyptic number.

308998639 is a deficient number, since it is larger than the sum of its proper divisors (5830217).

308998639 is an equidigital number, since it uses as much as digits as its factorization.

308998639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5830216.

The product of its (nonzero) digits is 2519424, while the sum is 55.

The square root of 308998639 is about 17578.3571189119. The cubic root of 308998639 is about 676.0604375956.

The spelling of 308998639 in words is "three hundred eight million, nine hundred ninety-eight thousand, six hundred thirty-nine".