15399939994 has 8 divisors (see below), whose sum is σ = 23101015860. Its totient is φ = 7699601376.

The previous prime is 15399939911. The next prime is 15399940001. The reversal of 15399939994 is 49993999351.

It can be written as a sum of positive squares in 2 ways, for example, as 13991814369 + 1408125625 = 118287^2 + 37525^2 .

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

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, 128739 + ... + 217654.

Almost surely, 2^15399939994 is an apocalyptic number.

15399939994 is a deficient number, since it is larger than the sum of its proper divisors (7701075866).

15399939994 is a wasteful number, since it uses less digits than its factorization.

15399939994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 368624.

The product of its digits is 95659380, while the sum is 70.

The spelling of 15399939994 in words is "fifteen billion, three hundred ninety-nine million, nine hundred thirty-nine thousand, nine hundred ninety-four".