389491278 has 64 divisors (see below), whose sum is σ = 870089472. Its totient is φ = 115246080.

The previous prime is 389491259. The next prime is 389491309. The reversal of 389491278 is 872194983.

It is a self number, because there is not a number n which added to its sum of digits gives 389491278.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 531000 + ... + 531732.

It is an arithmetic number, because the mean of its divisors is an integer number (13595148).

Almost surely, 2^389491278 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 389491278, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (435044736).

389491278 is an abundant number, since it is smaller than the sum of its proper divisors (480598194).

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

389491278 is a wasteful number, since it uses less digits than its factorization.

389491278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 929.

The product of its digits is 870912, while the sum is 51.

The square root of 389491278 is about 19735.5333852420. The cubic root of 389491278 is about 730.2965443101.

The spelling of 389491278 in words is "three hundred eighty-nine million, four hundred ninety-one thousand, two hundred seventy-eight".