168978485818640 has 40 divisors (see below), whose sum is σ = 392885204760600. Its totient is φ = 67589635147776.

The previous prime is 168978485818609. The next prime is 168978485818673. The reversal of 168978485818640 is 46818584879861.

It can be written as a sum of positive squares in 4 ways, for example, as 20225239573504 + 148753246245136 = 4497248^2 + 12196444^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24392039 + ... + 30543878.

It is an arithmetic number, because the mean of its divisors is an integer number (9822130119015).

Almost surely, 2^{168978485818640} is an apocalyptic number.

168978485818640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

168978485818640 is an abundant number, since it is smaller than the sum of its proper divisors (223906718941960).

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

168978485818640 is a wasteful number, since it uses less digits than its factorization.

168978485818640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54974379 (or 54974373 counting only the distinct ones).

The product of its (nonzero) digits is 5945425920, while the sum is 83.

The spelling of 168978485818640 in words is "one hundred sixty-eight trillion, nine hundred seventy-eight billion, four hundred eighty-five million, eight hundred eighteen thousand, six hundred forty".