21791159219 has 4 divisors (see below), whose sum is σ = 21791702544. Its totient is φ = 21790615896.

The previous prime is 21791159209. The next prime is 21791159227. The reversal of 21791159219 is 91295119712.

It is a happy number.

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-21791159219 is a prime.

It is a super-2 number, since 2×21791159219² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21791159209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 206252 + ... + 293465.

It is an arithmetic number, because the mean of its divisors is an integer number (5447925636).

Almost surely, 2^21791159219 is an apocalyptic number.

21791159219 is a deficient number, since it is larger than the sum of its proper divisors (543325).

21791159219 is an equidigital number, since it uses as much as digits as its factorization.

21791159219 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 543324.

The product of its digits is 102060, while the sum is 47.

The spelling of 21791159219 in words is "twenty-one billion, seven hundred ninety-one million, one hundred fifty-nine thousand, two hundred nineteen".