640435572537 has 8 divisors (see below), whose sum is σ = 854340422304. Its totient is φ = 426743885568.

The previous prime is 640435572487. The next prime is 640435572547. The reversal of 640435572537 is 735275534046.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 640435572537 - 2⁶ = 640435572473 is a prime.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 640435572537.

It is not an unprimeable number, because it can be changed into a prime (640435572547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53283688 + ... + 53295705.

It is an arithmetic number, because the mean of its divisors is an integer number (106792552788).

Almost surely, 2^640435572537 is an apocalyptic number.

It is an amenable number.

640435572537 is a deficient number, since it is larger than the sum of its proper divisors (213904849767).

640435572537 is a wasteful number, since it uses less digits than its factorization.

640435572537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106581399.

The product of its (nonzero) digits is 10584000, while the sum is 51.

The spelling of 640435572537 in words is "six hundred forty billion, four hundred thirty-five million, five hundred seventy-two thousand, five hundred thirty-seven".