84778396640 has 72 divisors (see below), whose sum is σ = 232989222312. Its totient is φ = 29066876160.

The previous prime is 84778396609. The next prime is 84778396649. The reversal of 84778396640 is 4669387748.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84778396649) 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, 5398946 + ... + 5414625.

It is an arithmetic number, because the mean of its divisors is an integer number (3235961421).

Almost surely, 2^84778396640 is an apocalyptic number.

84778396640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

84778396640 is an abundant number, since it is smaller than the sum of its proper divisors (148210825672).

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

84778396640 is a wasteful number, since it uses less digits than its factorization.

84778396640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10813600 (or 10813585 counting only the distinct ones).

The product of its (nonzero) digits is 48771072, while the sum is 62.

The spelling of 84778396640 in words is "eighty-four billion, seven hundred seventy-eight million, three hundred ninety-six thousand, six hundred forty".