399528448 has 60 divisors (see below), whose sum is σ = 877580550. Its totient is φ = 181575680.

The previous prime is 399528443. The next prime is 399528461. The reversal of 399528448 is 844825993.

It can be written as a sum of positive squares in only one way, i.e., 234457344 + 165071104 = 15312^2 + 12848^2 .

It is a super-2 number, since 2×399528448² = 319245961522577408, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 399528395 and 399528404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399528443) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 58728 + ... + 65176.

Almost surely, 2^399528448 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 399528448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (438790275).

399528448 is an abundant number, since it is smaller than the sum of its proper divisors (478052102).

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

399528448 is an equidigital number, since it uses as much as digits as its factorization.

399528448 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6489 (or 6462 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 52.

The square root of 399528448 is about 19988.2077235554. The cubic root of 399528448 is about 736.5166504741.

It can be divided in two parts, 39952 and 8448, that added together give a square (48400 = 220²).

The spelling of 399528448 in words is "three hundred ninety-nine million, five hundred twenty-eight thousand, four hundred forty-eight".