399386018 has 4 divisors (see below), whose sum is σ = 599079030. Its totient is φ = 199693008.

The previous prime is 399385997. The next prime is 399386069. The reversal of 399386018 is 810683993.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 810683993 = 7 ⋅115811999.

It can be written as a sum of positive squares in only one way, i.e., 256416169 + 142969849 = 16013^2 + 11957^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99846503 + ... + 99846506.

Almost surely, 2^399386018 is an apocalyptic number.

399386018 is a deficient number, since it is larger than the sum of its proper divisors (199693012).

399386018 is a wasteful number, since it uses less digits than its factorization.

399386018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199693011.

The product of its (nonzero) digits is 279936, while the sum is 47.

The square root of 399386018 is about 19984.6445552579. The cubic root of 399386018 is about 736.4291185055.

The spelling of 399386018 in words is "three hundred ninety-nine million, three hundred eighty-six thousand, eighteen".