399318550 has 12 divisors (see below), whose sum is σ = 742732596. Its totient is φ = 159727400.

The previous prime is 399318529. The next prime is 399318551. The reversal of 399318550 is 55813993.

It is a junction number, because it is equal to n+sod(n) for n = 399318497 and 399318506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399318551) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3993136 + ... + 3993235.

It is an arithmetic number, because the mean of its divisors is an integer number (61894383).

Almost surely, 2^399318550 is an apocalyptic number.

399318550 is a deficient number, since it is larger than the sum of its proper divisors (343414046).

399318550 is a wasteful number, since it uses less digits than its factorization.

399318550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7986383 (or 7986378 counting only the distinct ones).

The product of its (nonzero) digits is 145800, while the sum is 43.

The square root of 399318550 is about 19982.9564879674. The cubic root of 399318550 is about 736.3876480187.

The spelling of 399318550 in words is "three hundred ninety-nine million, three hundred eighteen thousand, five hundred fifty".