640604100646 has 16 divisors (see below), whose sum is σ = 1037260015200. Its totient is φ = 295811188288.

The previous prime is 640604100613. The next prime is 640604100649. The reversal of 640604100646 is 646001406046.

It is a happy number.

640604100646 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×640604100646² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640604100649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 240105151 + ... + 240107818.

It is an arithmetic number, because the mean of its divisors is an integer number (64828750950).

Almost surely, 2^640604100646 is an apocalyptic number.

640604100646 is a deficient number, since it is larger than the sum of its proper divisors (396655914554).

640604100646 is a wasteful number, since it uses less digits than its factorization.

640604100646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 480213023.

The product of its (nonzero) digits is 82944, while the sum is 37.

The spelling of 640604100646 in words is "six hundred forty billion, six hundred four million, one hundred thousand, six hundred forty-six".