19997975 has 12 divisors (see below), whose sum is σ = 26103240. Its totient is φ = 15156000.

The previous prime is 19997963. The next prime is 19997993. The reversal of 19997975 is 57979991.

It is not a de Polignac number, because 19997975 - 2⁶ = 19997911 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19997975.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20576 + ... + 21525.

It is an arithmetic number, because the mean of its divisors is an integer number (2175270).

Almost surely, 2^19997975 is an apocalyptic number.

19997975 is a deficient number, since it is larger than the sum of its proper divisors (6105265).

19997975 is a wasteful number, since it uses less digits than its factorization.

19997975 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42130 (or 42125 counting only the distinct ones).

The product of its digits is 1607445, while the sum is 56.

The square root of 19997975 is about 4471.9095473858. The cubic root of 19997975 is about 271.4326001908.

The spelling of 19997975 in words is "nineteen million, nine hundred ninety-seven thousand, nine hundred seventy-five".