664341643 has 4 divisors (see below), whose sum is σ = 759247600. Its totient is φ = 569435688.

The previous prime is 664341617. The next prime is 664341647. The reversal of 664341643 is 346143466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 346143466 = 2 ⋅173071733.

It is a cyclic number.

It is not a de Polignac number, because 664341643 - 2⁵ = 664341611 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664341647) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47452968 + ... + 47452981.

It is an arithmetic number, because the mean of its divisors is an integer number (189811900).

Almost surely, 2^664341643 is an apocalyptic number.

664341643 is a deficient number, since it is larger than the sum of its proper divisors (94905957).

664341643 is an equidigital number, since it uses as much as digits as its factorization.

664341643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94905956.

The product of its digits is 124416, while the sum is 37.

The square root of 664341643 is about 25774.8257608078. The cubic root of 664341643 is about 872.5637342298.

The spelling of 664341643 in words is "six hundred sixty-four million, three hundred forty-one thousand, six hundred forty-three".