399619072 has 44 divisors (see below), whose sum is σ = 826455780. Its totient is φ = 192905216.

The previous prime is 399619069. The next prime is 399619079. The reversal of 399619072 is 270916993.

It can be written as a sum of positive squares in 2 ways, for example, as 342102016 + 57517056 = 18496^2 + 7584^2 .

It is a super-2 number, since 2×399619072² = 319390805412282368, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399619079) 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, 22968 + ... + 36424.

Almost surely, 2^399619072 is an apocalyptic number.

399619072 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 399619072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (413227890).

399619072 is an abundant number, since it is smaller than the sum of its proper divisors (426836708).

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

399619072 is a wasteful number, since it uses less digits than its factorization.

399619072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13506 (or 13488 counting only the distinct ones).

The product of its (nonzero) digits is 183708, while the sum is 46.

The square root of 399619072 is about 19990.4745316363. The cubic root of 399619072 is about 736.5723336504.

The spelling of 399619072 in words is "three hundred ninety-nine million, six hundred nineteen thousand, seventy-two".