778869 has 32 divisors (see below), whose sum is σ = 1424640. Its totient is φ = 409536.

The previous prime is 778847. The next prime is 778871. The reversal of 778869 is 968877.

It is not a de Polignac number, because 778869 - 2⁹ = 778357 is a prime.

It is a super-2 number, since 2×778869² = 1213273838322, which contains 22 as substring.

778869 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (778819) 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, 2299 + ... + 2615.

It is an arithmetic number, because the mean of its divisors is an integer number (44520).

2⁷⁷⁸⁸⁶⁹ is an apocalyptic number.

It is an amenable number.

778869 is a deficient number, since it is larger than the sum of its proper divisors (645771).

778869 is a wasteful number, since it uses less digits than its factorization.

778869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 346 (or 340 counting only the distinct ones).

The product of its digits is 169344, while the sum is 45.

The square root of 778869 is about 882.5355516918. The cubic root of 778869 is about 92.0071276771.

The spelling of 778869 in words is "seven hundred seventy-eight thousand, eight hundred sixty-nine".