978644491776 has 320 divisors, whose sum is σ = 3454643174400. Its totient is φ = 267455029248.

The previous prime is 978644491711. The next prime is 978644491819. The reversal of 978644491776 is 677194446879.

978644491776 is a `hidden beast` number, since 9 + 7 + 8 + 6 + 4 + 449 + 177 + 6 = 666.

978644491776 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2005810 + ... + 2445518.

It is an arithmetic number, because the mean of its divisors is an integer number (10795759920).

Almost surely, 2^978644491776 is an apocalyptic number.

978644491776 is a gapful number since it is divisible by the number (96) 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 978644491776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1727321587200).

978644491776 is an abundant number, since it is smaller than the sum of its proper divisors (2475998682624).

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

978644491776 is a wasteful number, since it uses less digits than its factorization.

978644491776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 439766 (or 439744 counting only the distinct ones).

The product of its digits is 512096256, while the sum is 72.

The spelling of 978644491776 in words is "nine hundred seventy-eight billion, six hundred forty-four million, four hundred ninety-one thousand, seven hundred seventy-six".