390401280 has 108 divisors (see below), whose sum is σ = 1350787620. Its totient is φ = 104103936.

The previous prime is 390401269. The next prime is 390401293. The reversal of 390401280 is 82104093.

It can be written as a sum of positive squares in 2 ways, for example, as 275825664 + 114575616 = 16608^2 + 10704^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5425 + ... + 28464.

Almost surely, 2^390401280 is an apocalyptic number.

390401280 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 390401280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (675393810).

390401280 is an abundant number, since it is smaller than the sum of its proper divisors (960386340).

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

390401280 is a wasteful number, since it uses less digits than its factorization.

390401280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33916 (or 33899 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 390401280 is about 19758.5748473922. The cubic root of 390401280 is about 730.8648535031.

The spelling of 390401280 in words is "three hundred ninety million, four hundred one thousand, two hundred eighty".