18190226 has 4 divisors (see below), whose sum is σ = 27285342. Its totient is φ = 9095112.

The previous prime is 18190223. The next prime is 18190241. The reversal of 18190226 is 62209181.

It is a Cunningham number, because it is equal to 4265²+1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 62209181 = 23 ⋅2704747.

It can be written as a sum of positive squares in only one way, i.e., 18190225 + 1 = 4265^2 + 1^2 .

It is not an unprimeable number, because it can be changed into a prime (18190223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4547555 + ... + 4547558.

Almost surely, 2^18190226 is an apocalyptic number.

18190226 is a deficient number, since it is larger than the sum of its proper divisors (9095116).

18190226 is an equidigital number, since it uses as much as digits as its factorization.

18190226 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9095115.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 18190226 is about 4265.0001172333. Note that the first 3 decimals coincide. The cubic root of 18190226 is about 262.9941157295.

The spelling of 18190226 in words is "eighteen million, one hundred ninety thousand, two hundred twenty-six".