640830740045 has 18 divisors (see below), whose sum is σ = 816931680522. Its totient is φ = 482484939136.

The previous prime is 640830740023. The next prime is 640830740057. The reversal of 640830740045 is 540047038046.

640830740045 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 214645036804 + 426185703241 = 463298^2 + 652829^2 .

It is not a de Polignac number, because 640830740045 - 2¹⁸ = 640830477901 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 640830739984 and 640830740011.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 30419726 + ... + 30440784.

Almost surely, 2^640830740045 is an apocalyptic number.

It is an amenable number.

640830740045 is a deficient number, since it is larger than the sum of its proper divisors (176100940477).

640830740045 is an frugal number, since it uses more digits than its factorization.

640830740045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42157 (or 21081 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 41.

The spelling of 640830740045 in words is "six hundred forty billion, eight hundred thirty million, seven hundred forty thousand, forty-five".