18019967 has 16 divisors (see below), whose sum is σ = 21280512. Its totient is φ = 14938560.

The previous prime is 18019943. The next prime is 18019993. The reversal of 18019967 is 76991081.

It is a happy number.

It is not a de Polignac number, because 18019967 - 2¹⁰ = 18018943 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18019907) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39203 + ... + 39659.

It is an arithmetic number, because the mean of its divisors is an integer number (1330032).

Almost surely, 2^18019967 is an apocalyptic number.

18019967 is a deficient number, since it is larger than the sum of its proper divisors (3260545).

18019967 is a wasteful number, since it uses less digits than its factorization.

18019967 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 638.

The product of its (nonzero) digits is 27216, while the sum is 41.

The square root of 18019967 is about 4244.9931684280. The cubic root of 18019967 is about 262.1710079513.

The spelling of 18019967 in words is "eighteen million, nineteen thousand, nine hundred sixty-seven".