991140680 has 32 divisors (see below), whose sum is σ = 2302007040. Its totient is φ = 383666880.

The previous prime is 991140659. The next prime is 991140727. The reversal of 991140680 is 86041199.

It is a happy number.

991140680 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 398414 + ... + 400893.

It is an arithmetic number, because the mean of its divisors is an integer number (71937720).

Almost surely, 2^991140680 is an apocalyptic number.

It is an amenable number.

991140680 is an abundant number, since it is smaller than the sum of its proper divisors (1310866360).

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

991140680 is a wasteful number, since it uses less digits than its factorization.

991140680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 799349 (or 799345 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 38.

The square root of 991140680 is about 31482.3868218406. The cubic root of 991140680 is about 997.0381293166.

The spelling of 991140680 in words is "nine hundred ninety-one million, one hundred forty thousand, six hundred eighty".