18566730394 has 4 divisors (see below), whose sum is σ = 27850095594. Its totient is φ = 9283365196.

The previous prime is 18566730373. The next prime is 18566730409. The reversal of 18566730394 is 49303766581.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 11371449769 + 7195280625 = 106637^2 + 84825^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4641682597 + ... + 4641682600.

Almost surely, 2^18566730394 is an apocalyptic number.

18566730394 is a deficient number, since it is larger than the sum of its proper divisors (9283365200).

18566730394 is an equidigital number, since it uses as much as digits as its factorization.

18566730394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9283365199.

The product of its (nonzero) digits is 3265920, while the sum is 52.

The spelling of 18566730394 in words is "eighteen billion, five hundred sixty-six million, seven hundred thirty thousand, three hundred ninety-four".