391055772 has 12 divisors (see below), whose sum is σ = 912463496. Its totient is φ = 130351920.

The previous prime is 391055761. The next prime is 391055773. The reversal of 391055772 is 277550193.

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 391055772.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391055773) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16293979 + ... + 16294002.

Almost surely, 2^391055772 is an apocalyptic number.

It is an amenable number.

391055772 is an abundant number, since it is smaller than the sum of its proper divisors (521407724).

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

391055772 is a wasteful number, since it uses less digits than its factorization.

391055772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32587988 (or 32587986 counting only the distinct ones).

The product of its (nonzero) digits is 66150, while the sum is 39.

The square root of 391055772 is about 19775.1301386363. The cubic root of 391055772 is about 731.2730472976.

The spelling of 391055772 in words is "three hundred ninety-one million, fifty-five thousand, seven hundred seventy-two".