778204980 has 144 divisors (see below), whose sum is σ = 2705923584. Its totient is φ = 177338880.

The previous prime is 778204967. The next prime is 778204981. The reversal of 778204980 is 89402877.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (778204981) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 542344 + ... + 543776.

It is an arithmetic number, because the mean of its divisors is an integer number (18791136).

Almost surely, 2^778204980 is an apocalyptic number.

778204980 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 778204980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1352961792).

778204980 is an abundant number, since it is smaller than the sum of its proper divisors (1927718604).

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

778204980 is a wasteful number, since it uses less digits than its factorization.

778204980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1886 (or 1881 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 45.

The square root of 778204980 is about 27896.3255644897. The cubic root of 778204980 is about 919.8097353864.

The spelling of 778204980 in words is "seven hundred seventy-eight million, two hundred four thousand, nine hundred eighty".