778648 has 16 divisors (see below), whose sum is σ = 1572480. Its totient is φ = 359328.

The previous prime is 778643. The next prime is 778663. The reversal of 778648 is 846877.

778648 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 778648.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (778643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3640 + ... + 3847.

It is an arithmetic number, because the mean of its divisors is an integer number (98280).

2⁷⁷⁸⁶⁴⁸ is an apocalyptic number.

It is an amenable number.

778648 is an abundant number, since it is smaller than the sum of its proper divisors (793832).

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

778648 is a wasteful number, since it uses less digits than its factorization.

778648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7506 (or 7502 counting only the distinct ones).

The product of its digits is 75264, while the sum is 40.

The square root of 778648 is about 882.4103353882. The cubic root of 778648 is about 91.9984246737.

Adding to 778648 its sum of digits (40), we get a cube (778688 = 92³).

The spelling of 778648 in words is "seven hundred seventy-eight thousand, six hundred forty-eight".