640842360723180 has 2304 divisors, whose sum is σ = 2643838752522240. Its totient is φ = 121674070425600.

The previous prime is 640842360723143. The next prime is 640842360723181. The reversal of 640842360723180 is 81327063248046.

640842360723180 is a `hidden beast` number, since 6 + 4 + 0 + 8 + 4 + 2 + 3 + 607 + 23 + 1 + 8 + 0 = 666.

It is not an unprimeable number, because it can be changed into a prime (640842360723181) by changing a digit.

It is a polite number, since it can be written in 767 ways as a sum of consecutive naturals, for example, 173341183092 + ... + 173341186788.

It is an arithmetic number, because the mean of its divisors is an integer number (1147499458560).

Almost surely, 2^{640842360723180} is an apocalyptic number.

640842360723180 is a gapful number since it is divisible by the number (60) 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 640842360723180, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1321919376261120).

640842360723180 is an abundant number, since it is smaller than the sum of its proper divisors (2002996391799060).

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

640842360723180 is a wasteful number, since it uses less digits than its factorization.

640842360723180 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4020 (or 4015 counting only the distinct ones).

The product of its (nonzero) digits is 9289728, while the sum is 54.

The spelling of 640842360723180 in words is "six hundred forty trillion, eight hundred forty-two billion, three hundred sixty million, seven hundred twenty-three thousand, one hundred eighty".