18540919 has 4 divisors (see below), whose sum is σ = 18550944. Its totient is φ = 18530896.

The previous prime is 18540917. The next prime is 18540923. The reversal of 18540919 is 91904581.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 18540919 - 2¹ = 18540917 is a prime.

It is a super-2 number, since 2×18540919² = 687531354729122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18540917) 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, 1342 + ... + 6235.

It is an arithmetic number, because the mean of its divisors is an integer number (4637736).

Almost surely, 2^18540919 is an apocalyptic number.

18540919 is a deficient number, since it is larger than the sum of its proper divisors (10025).

18540919 is an equidigital number, since it uses as much as digits as its factorization.

18540919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10024.

The product of its (nonzero) digits is 12960, while the sum is 37.

The square root of 18540919 is about 4305.9167432731. The cubic root of 18540919 is about 264.6734746546.

The spelling of 18540919 in words is "eighteen million, five hundred forty thousand, nine hundred nineteen".