978287984640 has 432 divisors, whose sum is σ = 3517564796928. Its totient is φ = 260834328576.

The previous prime is 978287984599. The next prime is 978287984689. The reversal of 978287984640 is 46489782879.

978287984640 is a `hidden beast` number, since 9 + 7 + 82 + 87 + 9 + 8 + 464 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (432).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 159249409 + ... + 159255551.

It is an arithmetic number, because the mean of its divisors is an integer number (8142511104).

Almost surely, 2^978287984640 is an apocalyptic number.

978287984640 is a gapful number since it is divisible by the number (90) 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 978287984640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1758782398464).

978287984640 is an abundant number, since it is smaller than the sum of its proper divisors (2539276812288).

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

978287984640 is an frugal number, since it uses more digits than its factorization.

978287984640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6197 (or 6153 counting only the distinct ones).

The product of its (nonzero) digits is 390168576, while the sum is 72.

The spelling of 978287984640 in words is "nine hundred seventy-eight billion, two hundred eighty-seven million, nine hundred eighty-four thousand, six hundred forty".