21243064 has 32 divisors (see below), whose sum is σ = 44398800. Its totient is φ = 9469440.

The previous prime is 21243059. The next prime is 21243077. The reversal of 21243064 is 46034212.

It is a happy number.

It is a congruent number.

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, 1527 + ... + 6694.

Almost surely, 2^21243064 is an apocalyptic number.

It is an amenable number.

21243064 is an abundant number, since it is smaller than the sum of its proper divisors (23155736).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21243064 is a wasteful number, since it uses less digits than its factorization.

21243064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8263 (or 8259 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 21243064 is about 4609.0198524198. The cubic root of 21243064 is about 276.9527738174.

Adding to 21243064 its reverse (46034212), we get a palindrome (67277276).

The spelling of 21243064 in words is "twenty-one million, two hundred forty-three thousand, sixty-four".