19868921 has 8 divisors (see below), whose sum is σ = 20573184. Its totient is φ = 19176480.

The previous prime is 19868897. The next prime is 19868939. The reversal of 19868921 is 12986891.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19868921 - 2¹⁸ = 19606777 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (19868621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 536 + ... + 6326.

It is an arithmetic number, because the mean of its divisors is an integer number (2571648).

Almost surely, 2^19868921 is an apocalyptic number.

It is an amenable number.

19868921 is a deficient number, since it is larger than the sum of its proper divisors (704263).

19868921 is an equidigital number, since it uses as much as digits as its factorization.

19868921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5911.

The product of its digits is 62208, while the sum is 44.

The square root of 19868921 is about 4457.4567861057. The cubic root of 19868921 is about 270.8474561682.

The spelling of 19868921 in words is "nineteen million, eight hundred sixty-eight thousand, nine hundred twenty-one".