399366280 has 64 divisors (see below), whose sum is σ = 919512000. Its totient is φ = 156059904.

The previous prime is 399366269. The next prime is 399366287. The reversal of 399366280 is 82663993.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 399366280.

It is not an unprimeable number, because it can be changed into a prime (399366287) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 464491 + ... + 465349.

It is an arithmetic number, because the mean of its divisors is an integer number (14367375).

Almost surely, 2^399366280 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 399366280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (459756000).

399366280 is an abundant number, since it is smaller than the sum of its proper divisors (520145720).

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

399366280 is a wasteful number, since it uses less digits than its factorization.

399366280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1126 (or 1122 counting only the distinct ones).

The product of its (nonzero) digits is 419904, while the sum is 46.

The square root of 399366280 is about 19984.1507200081. The cubic root of 399366280 is about 736.4169866525.

The spelling of 399366280 in words is "three hundred ninety-nine million, three hundred sixty-six thousand, two hundred eighty".