19898071 has 4 divisors (see below), whose sum is σ = 19921392. Its totient is φ = 19874752.

The previous prime is 19898051. The next prime is 19898093. The reversal of 19898071 is 17089891.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19898071 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 (19898051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10330 + ... + 12103.

It is an arithmetic number, because the mean of its divisors is an integer number (4980348).

Almost surely, 2^19898071 is an apocalyptic number.

19898071 is a deficient number, since it is larger than the sum of its proper divisors (23321).

19898071 is an equidigital number, since it uses as much as digits as its factorization.

19898071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23320.

The product of its (nonzero) digits is 36288, while the sum is 43.

The square root of 19898071 is about 4460.7253894406. The cubic root of 19898071 is about 270.9798462702.

The spelling of 19898071 in words is "nineteen million, eight hundred ninety-eight thousand, seventy-one".