640135433560 has 192 divisors, whose sum is σ = 1738747425600. Its totient is φ = 211232480256.

The previous prime is 640135433543. The next prime is 640135433563. The reversal of 640135433560 is 65334531046.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640135433563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 18000517 + ... + 18036043.

It is an arithmetic number, because the mean of its divisors is an integer number (9055976175).

Almost surely, 2^640135433560 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 640135433560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (869373712800).

640135433560 is an abundant number, since it is smaller than the sum of its proper divisors (1098611992040).

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

640135433560 is a wasteful number, since it uses less digits than its factorization.

640135433560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35898 (or 35887 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 40.

The spelling of 640135433560 in words is "six hundred forty billion, one hundred thirty-five million, four hundred thirty-three thousand, five hundred sixty".