664620563 has 12 divisors (see below), whose sum is σ = 696022464. Its totient is φ = 633973200.

The previous prime is 664620511. The next prime is 664620571. The reversal of 664620563 is 365026466.

It is not a de Polignac number, because 664620563 - 2²⁸ = 396185107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664620263) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 154145 + ... + 158397.

It is an arithmetic number, because the mean of its divisors is an integer number (58001872).

Almost surely, 2^664620563 is an apocalyptic number.

664620563 is a deficient number, since it is larger than the sum of its proper divisors (31401901).

664620563 is an equidigital number, since it uses as much as digits as its factorization.

664620563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4426 (or 4355 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 38.

The square root of 664620563 is about 25780.2358988431. The cubic root of 664620563 is about 872.6858307582.

The spelling of 664620563 in words is "six hundred sixty-four million, six hundred twenty thousand, five hundred sixty-three".