791390721 has 16 divisors (see below), whose sum is σ = 1160183808. Its totient is φ = 475851600.

The previous prime is 791390711. The next prime is 791390771. The reversal of 791390721 is 127093197.

It is not a de Polignac number, because 791390721 - 2⁵ = 791390689 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 791390721.

It is not an unprimeable number, because it can be changed into a prime (791390711) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 90225 + ... + 98606.

It is an arithmetic number, because the mean of its divisors is an integer number (72511488).

Almost surely, 2^791390721 is an apocalyptic number.

It is an amenable number.

791390721 is a deficient number, since it is larger than the sum of its proper divisors (368793087).

791390721 is a wasteful number, since it uses less digits than its factorization.

791390721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188972.

The product of its (nonzero) digits is 23814, while the sum is 39.

The square root of 791390721 is about 28131.6675829927. The cubic root of 791390721 is about 924.9756880876.

The spelling of 791390721 in words is "seven hundred ninety-one million, three hundred ninety thousand, seven hundred twenty-one".