399443670 has 64 divisors (see below), whose sum is σ = 1072440000. Its totient is φ = 105792768.

The previous prime is 399443623. The next prime is 399443687. The reversal of 399443670 is 76344993.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 35266 + ... + 45194.

It is an arithmetic number, because the mean of its divisors is an integer number (16756875).

Almost surely, 2^399443670 is an apocalyptic number.

399443670 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 399443670, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (536220000).

399443670 is an abundant number, since it is smaller than the sum of its proper divisors (672996330).

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

399443670 is a wasteful number, since it uses less digits than its factorization.

399443670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10094 (or 10088 counting only the distinct ones).

The product of its (nonzero) digits is 489888, while the sum is 45.

The square root of 399443670 is about 19986.0869106486. The cubic root of 399443670 is about 736.4645517012.

The spelling of 399443670 in words is "three hundred ninety-nine million, four hundred forty-three thousand, six hundred seventy".