308968138 has 8 divisors (see below), whose sum is σ = 464268420. Its totient is φ = 154212000.

The previous prime is 308968129. The next prime is 308968181. The reversal of 308968138 is 831869803.

It can be written as a sum of positive squares in 2 ways, for example, as 306845289 + 2122849 = 17517^2 + 1457^2 .

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

It is a super-2 number, since 2×308968138² = 190922620598374088, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 134613 + ... + 136888.

Almost surely, 2^308968138 is an apocalyptic number.

308968138 is a deficient number, since it is larger than the sum of its proper divisors (155300282).

308968138 is a wasteful number, since it uses less digits than its factorization.

308968138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272072.

The product of its (nonzero) digits is 248832, while the sum is 46.

The square root of 308968138 is about 17577.4895249578. The cubic root of 308968138 is about 676.0381924082.

The spelling of 308968138 in words is "three hundred eight million, nine hundred sixty-eight thousand, one hundred thirty-eight".