391995560 has 64 divisors (see below), whose sum is σ = 976605120. Its totient is φ = 140405760.

The previous prime is 391995431. The next prime is 391995671. The reversal of 391995560 is 65599193.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22832 + ... + 36128.

It is an arithmetic number, because the mean of its divisors is an integer number (15259455).

Almost surely, 2^391995560 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 391995560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (488302560).

391995560 is an abundant number, since it is smaller than the sum of its proper divisors (584609560).

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

391995560 is a wasteful number, since it uses less digits than its factorization.

391995560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13386 (or 13382 counting only the distinct ones).

The product of its (nonzero) digits is 328050, while the sum is 47.

The square root of 391995560 is about 19798.8777459734. The cubic root of 391995560 is about 731.8583788450.

The spelling of 391995560 in words is "three hundred ninety-one million, nine hundred ninety-five thousand, five hundred sixty".