640254123644 has 12 divisors (see below), whose sum is σ = 1122066204168. Its totient is φ = 319663779600.

The previous prime is 640254123617. The next prime is 640254123689. The reversal of 640254123644 is 446321452046.

640254123644 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (41) 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 3 ways as a sum of consecutive naturals, for example, 115817447 + ... + 115822974.

It is an arithmetic number, because the mean of its divisors is an integer number (93505517014).

Almost surely, 2^640254123644 is an apocalyptic number.

It is an amenable number.

640254123644 is a deficient number, since it is larger than the sum of its proper divisors (481812080524).

640254123644 is a wasteful number, since it uses less digits than its factorization.

640254123644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231641116 (or 231641114 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 41.

The spelling of 640254123644 in words is "six hundred forty billion, two hundred fifty-four million, one hundred twenty-three thousand, six hundred forty-four".