640409730012 has 36 divisors (see below), whose sum is σ = 1743337599640. Its totient is φ = 197049147552.

The previous prime is 640409730011. The next prime is 640409730017. The reversal of 640409730012 is 210037904046.

640409730012 is a `hidden beast` number, since 640 + 4 + 0 + 9 + 7 + 3 + 0 + 0 + 1 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640409730011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 684197962 + ... + 684198897.

Almost surely, 2^640409730012 is an apocalyptic number.

It is an amenable number.

640409730012 is an abundant number, since it is smaller than the sum of its proper divisors (1102927869628).

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

640409730012 is a wasteful number, since it uses less digits than its factorization.

640409730012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1368396882 (or 1368396877 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The spelling of 640409730012 in words is "six hundred forty billion, four hundred nine million, seven hundred thirty thousand, twelve".