19998165 has 32 divisors (see below), whose sum is σ = 36748800. Its totient is φ = 9184320.

The previous prime is 19998163. The next prime is 19998169. The reversal of 19998165 is 56189991.

It is not a de Polignac number, because 19998165 - 2¹ = 19998163 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19998161) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 55 + ... + 6324.

It is an arithmetic number, because the mean of its divisors is an integer number (1148400).

Almost surely, 2^19998165 is an apocalyptic number.

19998165 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

19998165 is a deficient number, since it is larger than the sum of its proper divisors (16750635).

19998165 is a wasteful number, since it uses less digits than its factorization.

19998165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6417.

The product of its digits is 174960, while the sum is 48.

The square root of 19998165 is about 4471.9307910566. The cubic root of 19998165 is about 271.4334598117.

The spelling of 19998165 in words is "nineteen million, nine hundred ninety-eight thousand, one hundred sixty-five".