21819159 has 16 divisors (see below), whose sum is σ = 33199840. Its totient is φ = 14152320.

The previous prime is 21819137. The next prime is 21819169. The reversal of 21819159 is 95191812.

It is not a de Polignac number, because 21819159 - 2⁹ = 21818647 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 (21819169) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9922 + ... + 11919.

It is an arithmetic number, because the mean of its divisors is an integer number (2074990).

Almost surely, 2^21819159 is an apocalyptic number.

21819159 is a deficient number, since it is larger than the sum of its proper divisors (11380681).

21819159 is a wasteful number, since it uses less digits than its factorization.

21819159 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21887 (or 21881 counting only the distinct ones).

The product of its digits is 6480, while the sum is 36.

The square root of 21819159 is about 4671.0982648623. The cubic root of 21819159 is about 279.4340567013.

The spelling of 21819159 in words is "twenty-one million, eight hundred nineteen thousand, one hundred fifty-nine".