18220237 has 8 divisors (see below), whose sum is σ = 20878272. Its totient is φ = 15576000.

The previous prime is 18220193. The next prime is 18220247. The reversal of 18220237 is 73202281.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18220237 - 2⁷ = 18220109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18220247) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 439 + ... + 6052.

It is an arithmetic number, because the mean of its divisors is an integer number (2609784).

Almost surely, 2^18220237 is an apocalyptic number.

It is an amenable number.

18220237 is a deficient number, since it is larger than the sum of its proper divisors (2658035).

18220237 is an equidigital number, since it uses as much as digits as its factorization.

18220237 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6899.

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 18220237 is about 4268.5169555713. The cubic root of 18220237 is about 263.1386691800.

The spelling of 18220237 in words is "eighteen million, two hundred twenty thousand, two hundred thirty-seven".