399768560 has 80 divisors (see below), whose sum is σ = 964319232. Its totient is φ = 153964800.

The previous prime is 399768557. The next prime is 399768571. The reversal of 399768560 is 65867993.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 820637 + ... + 821123.

Almost surely, 2^399768560 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 399768560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (482159616).

399768560 is an abundant number, since it is smaller than the sum of its proper divisors (564550672).

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

399768560 is a wasteful number, since it uses less digits than its factorization.

399768560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 862 (or 856 counting only the distinct ones).

The product of its (nonzero) digits is 2449440, while the sum is 53.

The square root of 399768560 is about 19994.2131628129. The cubic root of 399768560 is about 736.6641669369.

The spelling of 399768560 in words is "three hundred ninety-nine million, seven hundred sixty-eight thousand, five hundred sixty".