18190819 has 8 divisors (see below), whose sum is σ = 18664992. Its totient is φ = 17721600.

The previous prime is 18190811. The next prime is 18190841. The reversal of 18190819 is 91809181.

It is a happy number.

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 18190819 - 2³ = 18190811 is a prime.

It is a super-2 number, since 2×18190819² = 661811791781522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18190811) 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, 6867 + ... + 9139.

It is an arithmetic number, because the mean of its divisors is an integer number (2333124).

Almost surely, 2^18190819 is an apocalyptic number.

18190819 is a deficient number, since it is larger than the sum of its proper divisors (474173).

18190819 is a wasteful number, since it uses less digits than its factorization.

18190819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2477.

The product of its (nonzero) digits is 5184, while the sum is 37.

The square root of 18190819 is about 4265.0696360083. The cubic root of 18190819 is about 262.9969735612.

The spelling of 18190819 in words is "eighteen million, one hundred ninety thousand, eight hundred nineteen".