640105026144 has 96 divisors (see below), whose sum is σ = 1780124695776. Its totient is φ = 200703344640.

The previous prime is 640105026139. The next prime is 640105026149. The reversal of 640105026144 is 441620501046.

It is an interprime number because it is at equal distance from previous prime (640105026139) and next prime (640105026149).

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640105026149) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2789704 + ... + 3010424.

It is an arithmetic number, because the mean of its divisors is an integer number (18542965581).

Almost surely, 2^640105026144 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 640105026144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (890062347888).

640105026144 is an abundant number, since it is smaller than the sum of its proper divisors (1140019669632).

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

640105026144 is a wasteful number, since it uses less digits than its factorization.

640105026144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222528 (or 222520 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 33.

The spelling of 640105026144 in words is "six hundred forty billion, one hundred five million, twenty-six thousand, one hundred forty-four".