640409730047 has 6 divisors (see below), whose sum is σ = 680296841568. Its totient is φ = 602738569184.

The previous prime is 640409730019. The next prime is 640409730109. The reversal of 640409730047 is 740037904046.

It is not a de Polignac number, because 640409730047 - 2¹⁸ = 640409467903 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640409730007) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1107975023 + ... + 1107975600.

It is an arithmetic number, because the mean of its divisors is an integer number (113382806928).

Almost surely, 2^640409730047 is an apocalyptic number.

640409730047 is a deficient number, since it is larger than the sum of its proper divisors (39887111521).

640409730047 is a wasteful number, since it uses less digits than its factorization.

640409730047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2215950657 (or 2215950640 counting only the distinct ones).

The product of its (nonzero) digits is 508032, while the sum is 44.

The spelling of 640409730047 in words is "six hundred forty billion, four hundred nine million, seven hundred thirty thousand, forty-seven".