21323115 has 64 divisors (see below), whose sum is σ = 42094080. Its totient is φ = 10154880.

The previous prime is 21323089. The next prime is 21323129. The reversal of 21323115 is 51132312.

It is not a de Polignac number, because 21323115 - 2¹¹ = 21321067 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 123169 + ... + 123341.

It is an arithmetic number, because the mean of its divisors is an integer number (657720).

Almost surely, 2^21323115 is an apocalyptic number.

21323115 is a deficient number, since it is larger than the sum of its proper divisors (20770965).

21323115 is a wasteful number, since it uses less digits than its factorization.

21323115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281 (or 275 counting only the distinct ones).

The product of its digits is 180, while the sum is 18.

The square root of 21323115 is about 4617.6958539947. The cubic root of 21323115 is about 277.3002214395.

Adding to 21323115 its reverse (51132312), we get a palindrome (72455427).

The spelling of 21323115 in words is "twenty-one million, three hundred twenty-three thousand, one hundred fifteen".