19998016 has 14 divisors (see below), whose sum is σ = 39683690. Its totient is φ = 9998976.

The previous prime is 19997993. The next prime is 19998029. The reversal of 19998016 is 61089991.

It can be written as a sum of positive squares in only one way, i.e., 18318400 + 1679616 = 4280^2 + 1296^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156171 + ... + 156298.

Almost surely, 2^19998016 is an apocalyptic number.

19998016 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

19998016 is a deficient number, since it is larger than the sum of its proper divisors (19685674).

19998016 is an equidigital number, since it uses as much as digits as its factorization.

19998016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 312481 (or 312471 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 43.

The square root of 19998016 is about 4471.9141315549. The cubic root of 19998016 is about 271.4327856884.

Subtracting from 19998016 its product of nonzero digits (34992), we obtain a square (19963024 = 4468²).

The spelling of 19998016 in words is "nineteen million, nine hundred ninety-eight thousand, sixteen".