817942745 has 16 divisors (see below), whose sum is σ = 991215360. Its totient is φ = 647923584.

The previous prime is 817942733. The next prime is 817942759. The reversal of 817942745 is 547249718.

It is a cyclic number.

It is not a de Polignac number, because 817942745 - 2⁴ = 817942729 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 817942745.

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, 315866 + ... + 318444.

It is an arithmetic number, because the mean of its divisors is an integer number (61950960).

Almost surely, 2^817942745 is an apocalyptic number.

It is an amenable number.

817942745 is a deficient number, since it is larger than the sum of its proper divisors (173272615).

817942745 is a wasteful number, since it uses less digits than its factorization.

817942745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3184.

The product of its digits is 564480, while the sum is 47.

The square root of 817942745 is about 28599.6983375699. The cubic root of 817942745 is about 935.2067545863.

The spelling of 817942745 in words is "eight hundred seventeen million, nine hundred forty-two thousand, seven hundred forty-five".