640143168 has 112 divisors (see below), whose sum is σ = 1983053184. Its totient is φ = 178421760.

The previous prime is 640143113. The next prime is 640143173. The reversal of 640143168 is 861341046.

It is a tau number, because it is divible by the number of its divisors (112).

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49296 + ... + 60912.

It is an arithmetic number, because the mean of its divisors is an integer number (17705832).

Almost surely, 2^640143168 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640143168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (991526592).

640143168 is an abundant number, since it is smaller than the sum of its proper divisors (1342910016).

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

640143168 is a wasteful number, since it uses less digits than its factorization.

640143168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11680 (or 11670 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 640143168 is about 25301.0507291693. The cubic root of 640143168 is about 861.8381308271.

The spelling of 640143168 in words is "six hundred forty million, one hundred forty-three thousand, one hundred sixty-eight".