21789115 has 8 divisors (see below), whose sum is σ = 26853840. Its totient is φ = 16960032.

The previous prime is 21789109. The next prime is 21789127. The reversal of 21789115 is 51198712.

It is a happy number.

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 21789115 - 2⁵ = 21789083 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58705 + ... + 59074.

It is an arithmetic number, because the mean of its divisors is an integer number (3356730).

Almost surely, 2^21789115 is an apocalyptic number.

21789115 is a deficient number, since it is larger than the sum of its proper divisors (5064725).

21789115 is a wasteful number, since it uses less digits than its factorization.

21789115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117821.

The product of its digits is 5040, while the sum is 34.

The square root of 21789115 is about 4667.8812109993. The cubic root of 21789115 is about 279.3057417484.

It can be divided in two parts, 21789 and 115, that added together give a square (21904 = 148²).

The spelling of 21789115 in words is "twenty-one million, seven hundred eighty-nine thousand, one hundred fifteen".