778811904 has 120 divisors (see below), whose sum is σ = 2420790372. Its totient is φ = 239616000.

The previous prime is 778811903. The next prime is 778811911. The reversal of 778811904 is 409118877.

It can be written as a sum of positive squares in 2 ways, for example, as 578306304 + 200505600 = 24048^2 + 14160^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 778811904.

It is not an unprimeable number, because it can be changed into a prime (778811903) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 53404 + ... + 66404.

Almost surely, 2^778811904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 778811904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1210395186).

778811904 is an abundant number, since it is smaller than the sum of its proper divisors (1641978468).

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

778811904 is a wasteful number, since it uses less digits than its factorization.

778811904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13038 (or 13019 counting only the distinct ones).

The product of its (nonzero) digits is 112896, while the sum is 45.

The square root of 778811904 is about 27907.2016511867. The cubic root of 778811904 is about 920.0487938834.

The spelling of 778811904 in words is "seven hundred seventy-eight million, eight hundred eleven thousand, nine hundred four".