399140280 has 576 divisors, whose sum is σ = 1757414880. Its totient is φ = 78059520.

The previous prime is 399140279. The next prime is 399140293. The reversal of 399140280 is 82041993.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 23478832 + ... + 23478848.

Almost surely, 2^399140280 is an apocalyptic number.

399140280 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 399140280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (878707440).

399140280 is an abundant number, since it is smaller than the sum of its proper divisors (1358274600).

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

399140280 is a wasteful number, since it uses less digits than its factorization.

399140280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81 (or 45 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 399140280 is about 19978.4954388462. The cubic root of 399140280 is about 736.2780484970.

The spelling of 399140280 in words is "three hundred ninety-nine million, one hundred forty thousand, two hundred eighty".