19861121 has 12 divisors (see below), whose sum is σ = 24109632. Its totient is φ = 16282728.

The previous prime is 19861109. The next prime is 19861147. The reversal of 19861121 is 12116891.

It is a de Polignac number, because none of the positive numbers 2^k-19861121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19861921) by changing a digit.

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, 7685 + ... + 9938.

It is an arithmetic number, because the mean of its divisors is an integer number (2009136).

Almost surely, 2^19861121 is an apocalyptic number.

It is an amenable number.

19861121 is a deficient number, since it is larger than the sum of its proper divisors (4248511).

19861121 is a wasteful number, since it uses less digits than its factorization.

19861121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17660 (or 17653 counting only the distinct ones).

The product of its digits is 864, while the sum is 29.

The square root of 19861121 is about 4456.5817618439. The cubic root of 19861121 is about 270.8120090719.

The spelling of 19861121 in words is "nineteen million, eight hundred sixty-one thousand, one hundred twenty-one".