18541618 has 4 divisors (see below), whose sum is σ = 27812430. Its totient is φ = 9270808.

The previous prime is 18541613. The next prime is 18541631. The reversal of 18541618 is 81614581.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81614581 = 907 ⋅89983.

It can be written as a sum of positive squares in only one way, i.e., 18173169 + 368449 = 4263^2 + 607^2 .

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (18541613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4635403 + ... + 4635406.

Almost surely, 2^18541618 is an apocalyptic number.

18541618 is a deficient number, since it is larger than the sum of its proper divisors (9270812).

18541618 is an equidigital number, since it uses as much as digits as its factorization.

18541618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9270811.

The product of its digits is 7680, while the sum is 34.

The square root of 18541618 is about 4305.9979098927. The cubic root of 18541618 is about 264.6768007112.

The spelling of 18541618 in words is "eighteen million, five hundred forty-one thousand, six hundred eighteen".