399775680 has 168 divisors, whose sum is σ = 1387156992. Its totient is φ = 105670656.

The previous prime is 399775657. The next prime is 399775709. The reversal of 399775680 is 86577993.

399775680 is a `hidden beast` number, since 3 + 9 + 9 + 77 + 568 + 0 = 666.

It is a zygodrome in base 4.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 365214 + ... + 366306.

Almost surely, 2^399775680 is an apocalyptic number.

399775680 is a gapful number since it is divisible by the number (30) 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 399775680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (693578496).

399775680 is an abundant number, since it is smaller than the sum of its proper divisors (987381312).

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

399775680 is a wasteful number, since it uses less digits than its factorization.

399775680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1243 (or 1230 counting only the distinct ones).

The product of its (nonzero) digits is 2857680, while the sum is 54.

The square root of 399775680 is about 19994.3912135379. The cubic root of 399775680 is about 736.6685403154.

The spelling of 399775680 in words is "three hundred ninety-nine million, seven hundred seventy-five thousand, six hundred eighty".