640833554160 has 240 divisors, whose sum is σ = 2239746897024. Its totient is φ = 170283638016.

The previous prime is 640833554113. The next prime is 640833554201. The reversal of 640833554160 is 61455338046.

640833554160 is a `hidden beast` number, since 6 + 4 + 0 + 8 + 33 + 554 + 1 + 60 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5443279 + ... + 5559761.

Almost surely, 2^640833554160 is an apocalyptic number.

640833554160 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 640833554160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1119873448512).

640833554160 is an abundant number, since it is smaller than the sum of its proper divisors (1598913342864).

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

640833554160 is a wasteful number, since it uses less digits than its factorization.

640833554160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116794 (or 116776 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 45.

The spelling of 640833554160 in words is "six hundred forty billion, eight hundred thirty-three million, five hundred fifty-four thousand, one hundred sixty".