391725056 has 30 divisors (see below), whose sum is σ = 783458970. Its totient is φ = 195854336.

The previous prime is 391725049. The next prime is 391725097. The reversal of 391725056 is 650527193.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 243859456 + 147865600 = 15616^2 + 12160^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4430 + ... + 28338.

It is an arithmetic number, because the mean of its divisors is an integer number (26115299).

Almost surely, 2^391725056 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 391725056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (391729485).

391725056 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

391725056 is an frugal number, since it uses more digits than its factorization.

391725056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23937 (or 23911 counting only the distinct ones).

The product of its (nonzero) digits is 56700, while the sum is 38.

The square root of 391725056 is about 19792.0452707647. The cubic root of 391725056 is about 731.6899958373.

The spelling of 391725056 in words is "three hundred ninety-one million, seven hundred twenty-five thousand, fifty-six".