18745906 has 4 divisors (see below), whose sum is σ = 28118862. Its totient is φ = 9372952.

The previous prime is 18745901. The next prime is 18745921. The reversal of 18745906 is 60954781.

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., 17715681 + 1030225 = 4209^2 + 1015^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (18745901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4686475 + ... + 4686478.

Almost surely, 2^18745906 is an apocalyptic number.

18745906 is a deficient number, since it is larger than the sum of its proper divisors (9372956).

18745906 is an equidigital number, since it uses as much as digits as its factorization.

18745906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9372955.

The product of its (nonzero) digits is 60480, while the sum is 40.

The square root of 18745906 is about 4329.6542587140. The cubic root of 18745906 is about 265.6453052252.

The spelling of 18745906 in words is "eighteen million, seven hundred forty-five thousand, nine hundred six".