640680440302 has 8 divisors (see below), whose sum is σ = 1098309326256. Its totient is φ = 274577331552.

The previous prime is 640680440299. The next prime is 640680440329. The reversal of 640680440302 is 203044086046.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22881444283 + ... + 22881444310.

It is an arithmetic number, because the mean of its divisors is an integer number (137288665782).

Almost surely, 2^640680440302 is an apocalyptic number.

640680440302 is a deficient number, since it is larger than the sum of its proper divisors (457628885954).

640680440302 is a wasteful number, since it uses less digits than its factorization.

640680440302 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45762888602.

The product of its (nonzero) digits is 110592, while the sum is 37.

The spelling of 640680440302 in words is "six hundred forty billion, six hundred eighty million, four hundred forty thousand, three hundred two".