778794861 has 32 divisors (see below), whose sum is σ = 1139396608. Its totient is φ = 470292480.

The previous prime is 778794859. The next prime is 778794901. The reversal of 778794861 is 168497877.

It is a happy number.

It is not a de Polignac number, because 778794861 - 2¹ = 778794859 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (778794851) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 479631 + ... + 481251.

It is an arithmetic number, because the mean of its divisors is an integer number (35606144).

Almost surely, 2^778794861 is an apocalyptic number.

It is an amenable number.

778794861 is a deficient number, since it is larger than the sum of its proper divisors (360601747).

778794861 is a wasteful number, since it uses less digits than its factorization.

778794861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1861.

The product of its digits is 4741632, while the sum is 57.

The square root of 778794861 is about 27906.8962982271. The cubic root of 778794861 is about 920.0420825898.

The spelling of 778794861 in words is "seven hundred seventy-eight million, seven hundred ninety-four thousand, eight hundred sixty-one".