640520226040 has 32 divisors (see below), whose sum is σ = 1503830098080. Its totient is φ = 245068607872.

The previous prime is 640520226023. The next prime is 640520226043. The reversal of 640520226040 is 40622025046.

It is a junction number, because it is equal to n+sod(n) for n = 640520225993 and 640520226011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640520226043) 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 7 ways as a sum of consecutive naturals, for example, 348107899 + ... + 348109738.

It is an arithmetic number, because the mean of its divisors is an integer number (46994690565).

Almost surely, 2^640520226040 is an apocalyptic number.

It is an amenable number.

640520226040 is an abundant number, since it is smaller than the sum of its proper divisors (863309872040).

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

640520226040 is a wasteful number, since it uses less digits than its factorization.

640520226040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 696217671 (or 696217667 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 31.

The spelling of 640520226040 in words is "six hundred forty billion, five hundred twenty million, two hundred twenty-six thousand, forty".