640340425544 has 16 divisors (see below), whose sum is σ = 1202460217200. Its totient is φ = 319684367632.

The previous prime is 640340425537. The next prime is 640340425547. The reversal of 640340425544 is 445524043046.

It is not an unprimeable number, because it can be changed into a prime (640340425547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 60725042 + ... + 60735585.

It is an arithmetic number, because the mean of its divisors is an integer number (75153763575).

Almost surely, 2^640340425544 is an apocalyptic number.

It is an amenable number.

640340425544 is a deficient number, since it is larger than the sum of its proper divisors (562119791656).

640340425544 is a wasteful number, since it uses less digits than its factorization.

640340425544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121461292 (or 121461288 counting only the distinct ones).

The product of its (nonzero) digits is 921600, while the sum is 41.

The spelling of 640340425544 in words is "six hundred forty billion, three hundred forty million, four hundred twenty-five thousand, five hundred forty-four".