399138 has 8 divisors (see below), whose sum is σ = 798288. Its totient is φ = 133044.

The previous prime is 399137. The next prime is 399149. The reversal of 399138 is 831993.

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

399138 is an admirable number.

It is a super-2 number, since 2×399138² = 318622286088, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 399099 and 399108.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 399138.

It is not an unprimeable number, because it can be changed into a prime (399131) 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, 33256 + ... + 33267.

It is an arithmetic number, because the mean of its divisors is an integer number (99786).

2³⁹⁹¹³⁸ is an apocalyptic number.

399138 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

399138 is a wasteful number, since it uses less digits than its factorization.

399138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66528.

The product of its digits is 5832, while the sum is 33.

The square root of 399138 is about 631.7736936594. The cubic root of 399138 is about 73.6276646553.

Adding to 399138 its sum of digits (33), we get a triangular number (399171 = T₈₉₃).

The spelling of 399138 in words is "three hundred ninety-nine thousand, one hundred thirty-eight".