641565723 has 16 divisors (see below), whose sum is σ = 902049920. Its totient is φ = 404476416.

The previous prime is 641565721. The next prime is 641565779. The reversal of 641565723 is 327565146.

It is not a de Polignac number, because 641565723 - 2¹ = 641565721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (641565721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23136 + ... + 42642.

It is an arithmetic number, because the mean of its divisors is an integer number (56378120).

Almost surely, 2^641565723 is an apocalyptic number.

641565723 is a deficient number, since it is larger than the sum of its proper divisors (260484197).

641565723 is a wasteful number, since it uses less digits than its factorization.

641565723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20106.

The product of its digits is 151200, while the sum is 39.

The square root of 641565723 is about 25329.1476958859. The cubic root of 641565723 is about 862.4760636919.

The spelling of 641565723 in words is "six hundred forty-one million, five hundred sixty-five thousand, seven hundred twenty-three".