778138580 has 48 divisors (see below), whose sum is σ = 1700455680. Its totient is φ = 298866048.

The previous prime is 778138579. The next prime is 778138583. The reversal of 778138580 is 85831877.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (778138583) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42011 + ... + 57629.

It is an arithmetic number, because the mean of its divisors is an integer number (35426160).

Almost surely, 2^778138580 is an apocalyptic number.

It is an amenable number.

778138580 is an abundant number, since it is smaller than the sum of its proper divisors (922317100).

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

778138580 is a wasteful number, since it uses less digits than its factorization.

778138580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15728 (or 15726 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 47.

The square root of 778138580 is about 27895.1354182051. The cubic root of 778138580 is about 919.7835738544.

The spelling of 778138580 in words is "seven hundred seventy-eight million, one hundred thirty-eight thousand, five hundred eighty".