664366243 has 4 divisors (see below), whose sum is σ = 665908128. Its totient is φ = 662824360.

The previous prime is 664366231. The next prime is 664366253. The reversal of 664366243 is 342663466.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 664366243 - 2⁹ = 664365731 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 664366196 and 664366205.

It is not an unprimeable number, because it can be changed into a prime (664366223) 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, 770296 + ... + 771157.

It is an arithmetic number, because the mean of its divisors is an integer number (166477032).

Almost surely, 2^664366243 is an apocalyptic number.

664366243 is a deficient number, since it is larger than the sum of its proper divisors (1541885).

664366243 is a wasteful number, since it uses less digits than its factorization.

664366243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1541884.

The product of its digits is 373248, while the sum is 40.

The square root of 664366243 is about 25775.3029662117. The cubic root of 664366243 is about 872.5745041919.

The spelling of 664366243 in words is "six hundred sixty-four million, three hundred sixty-six thousand, two hundred forty-three".