18481819 has 4 divisors (see below), whose sum is σ = 18494280. Its totient is φ = 18469360.

The previous prime is 18481807. The next prime is 18481831. The reversal of 18481819 is 91818481.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (18481807) and next prime (18481831).

It is a cyclic number.

It is not a de Polignac number, because 18481819 - 2²³ = 10093211 is a prime.

It is a super-2 number, since 2×18481819² = 683155267097522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18481919) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3649 + ... + 7090.

It is an arithmetic number, because the mean of its divisors is an integer number (4623570).

Almost surely, 2^18481819 is an apocalyptic number.

18481819 is a deficient number, since it is larger than the sum of its proper divisors (12461).

18481819 is a wasteful number, since it uses less digits than its factorization.

18481819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12460.

The product of its digits is 18432, while the sum is 40.

The square root of 18481819 is about 4299.0486156823. The cubic root of 18481819 is about 264.3919558526.

The spelling of 18481819 in words is "eighteen million, four hundred eighty-one thousand, eight hundred nineteen".