18670643 has 4 divisors (see below), whose sum is σ = 19104888. Its totient is φ = 18236400.

The previous prime is 18670637. The next prime is 18670661. The reversal of 18670643 is 34607681.

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 18670643 - 2⁶ = 18670579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18670343) 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, 217058 + ... + 217143.

It is an arithmetic number, because the mean of its divisors is an integer number (4776222).

Almost surely, 2^18670643 is an apocalyptic number.

18670643 is a deficient number, since it is larger than the sum of its proper divisors (434245).

18670643 is an equidigital number, since it uses as much as digits as its factorization.

18670643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 434244.

The product of its (nonzero) digits is 24192, while the sum is 35.

The square root of 18670643 is about 4320.9539456004. The cubic root of 18670643 is about 265.2893149722.

The spelling of 18670643 in words is "eighteen million, six hundred seventy thousand, six hundred forty-three".