640140635050 has 48 divisors (see below), whose sum is σ = 1361432237760. Its totient is φ = 219367733760.

The previous prime is 640140635039. The next prime is 640140635051. The reversal of 640140635050 is 50536041046.

It is a junction number, because it is equal to n+sod(n) for n = 640140634997 and 640140635015.

It is not an unprimeable number, because it can be changed into a prime (640140635051) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 252561 + ... + 1159339.

It is an arithmetic number, because the mean of its divisors is an integer number (28363171620).

Almost surely, 2^640140635050 is an apocalyptic number.

640140635050 is an abundant number, since it is smaller than the sum of its proper divisors (721291602710).

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

640140635050 is a wasteful number, since it uses less digits than its factorization.

640140635050 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 908815 (or 908810 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 34.

Adding to 640140635050 its reverse (50536041046), we get a palindrome (690676676096).

The spelling of 640140635050 in words is "six hundred forty billion, one hundred forty million, six hundred thirty-five thousand, fifty".