18218445 has 32 divisors (see below), whose sum is σ = 34003200. Its totient is φ = 8326080.

The previous prime is 18218423. The next prime is 18218449. The reversal of 18218445 is 54481281.

It is not a de Polignac number, because 18218445 - 2⁵ = 18218413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18218449) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3375 + ... + 6915.

It is an arithmetic number, because the mean of its divisors is an integer number (1062600).

Almost surely, 2^18218445 is an apocalyptic number.

18218445 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18218445 is a deficient number, since it is larger than the sum of its proper divisors (15784755).

18218445 is an equidigital number, since it uses as much as digits as its factorization.

18218445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3570 (or 3556 counting only the distinct ones).

The product of its digits is 10240, while the sum is 33.

The square root of 18218445 is about 4268.3070414393. The cubic root of 18218445 is about 263.1300421434.

The spelling of 18218445 in words is "eighteen million, two hundred eighteen thousand, four hundred forty-five".