399750 has 64 divisors (see below), whose sum is σ = 1100736. Its totient is φ = 96000.

The previous prime is 399739. The next prime is 399757. The reversal of 399750 is 57993.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399757) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9730 + ... + 9770.

It is an arithmetic number, because the mean of its divisors is an integer number (17199).

2³⁹⁹⁷⁵⁰ is an apocalyptic number.

399750 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 399750, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (550368).

399750 is an abundant number, since it is smaller than the sum of its proper divisors (700986).

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

399750 is a wasteful number, since it uses less digits than its factorization.

399750 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 8505, while the sum is 33.

The square root of 399750 is about 632.2578587886. The cubic root of 399750 is about 73.6652766425.

The spelling of 399750 in words is "three hundred ninety-nine thousand, seven hundred fifty".