399977280 has 168 divisors, whose sum is σ = 1423492200. Its totient is φ = 102961152.

The previous prime is 399977267. The next prime is 399977287. The reversal of 399977280 is 82779993.

It can be written as a sum of positive squares in 4 ways, for example, as 2214144 + 397763136 = 1488^2 + 19944^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399977287) 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, 81126 + ... + 85914.

Almost surely, 2^399977280 is an apocalyptic number.

399977280 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 399977280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (711746100).

399977280 is an abundant number, since it is smaller than the sum of its proper divisors (1023514920).

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

399977280 is a wasteful number, since it uses less digits than its factorization.

399977280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4841 (or 4828 counting only the distinct ones).

The product of its (nonzero) digits is 1714608, while the sum is 54.

The square root of 399977280 is about 19999.4319919342. The cubic root of 399977280 is about 736.7923492647.

The spelling of 399977280 in words is "three hundred ninety-nine million, nine hundred seventy-seven thousand, two hundred eighty".