18016997 has 4 divisors (see below), whose sum is σ = 18965280. Its totient is φ = 17068716.

The previous prime is 18016993. The next prime is 18017011. The reversal of 18016997 is 79961081.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 79961081 = 17 ⋅4703593.

It is a cyclic number.

It is not a de Polignac number, because 18016997 - 2² = 18016993 is a prime.

It is a super-2 number, since 2×18016997² = 649224361796018, 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 (18016993) 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 3 ways as a sum of consecutive naturals, for example, 474113 + ... + 474150.

It is an arithmetic number, because the mean of its divisors is an integer number (4741320).

Almost surely, 2^18016997 is an apocalyptic number.

It is an amenable number.

18016997 is a deficient number, since it is larger than the sum of its proper divisors (948283).

18016997 is an equidigital number, since it uses as much as digits as its factorization.

18016997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 948282.

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

The square root of 18016997 is about 4244.6433301280. The cubic root of 18016997 is about 262.1566037319.

The spelling of 18016997 in words is "eighteen million, sixteen thousand, nine hundred ninety-seven".