399117312 has 264 divisors, whose sum is σ = 1307983872. Its totient is φ = 116121600.

The previous prime is 399117293. The next prime is 399117319. The reversal of 399117312 is 213711993.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (264).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (399117319) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3142593 + ... + 3142719.

Almost surely, 2^399117312 is an apocalyptic number.

399117312 is a gapful number since it is divisible by the number (32) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 399117312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (653991936).

399117312 is an abundant number, since it is smaller than the sum of its proper divisors (908866560).

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

399117312 is a wasteful number, since it uses less digits than its factorization.

399117312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195 (or 174 counting only the distinct ones).

The product of its digits is 10206, while the sum is 36.

The square root of 399117312 is about 19977.9206125162. The cubic root of 399117312 is about 736.2639255103.

It can be divided in two parts, 399 and 117312, that added together give a palindrome (117711).

The spelling of 399117312 in words is "three hundred ninety-nine million, one hundred seventeen thousand, three hundred twelve".