18729019 has 16 divisors (see below), whose sum is σ = 20528640. Its totient is φ = 17019520.

The previous prime is 18728977. The next prime is 18729023. The reversal of 18729019 is 91092781.

It is a cyclic number.

It is not a de Polignac number, because 18729019 - 2¹⁹ = 18204731 is a prime.

It is a super-2 number, since 2×18729019² = 701552305404722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18729049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 71082 + ... + 71344.

It is an arithmetic number, because the mean of its divisors is an integer number (1283040).

Almost surely, 2^18729019 is an apocalyptic number.

18729019 is a deficient number, since it is larger than the sum of its proper divisors (1799621).

18729019 is a wasteful number, since it uses less digits than its factorization.

18729019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410.

The product of its (nonzero) digits is 9072, while the sum is 37.

The square root of 18729019 is about 4327.7036636073. The cubic root of 18729019 is about 265.5655135810.

The spelling of 18729019 in words is "eighteen million, seven hundred twenty-nine thousand, nineteen".