21066452 has 24 divisors (see below), whose sum is σ = 40334112. Its totient is φ = 9548000.

The previous prime is 21066449. The next prime is 21066457. The reversal of 21066452 is 25466012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21066457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29702 + ... + 30402.

It is an arithmetic number, because the mean of its divisors is an integer number (1680588).

Almost surely, 2^21066452 is an apocalyptic number.

21066452 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21066452 is a deficient number, since it is larger than the sum of its proper divisors (19267660).

21066452 is a wasteful number, since it uses less digits than its factorization.

21066452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1399 (or 1397 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 21066452 is about 4589.8204757921. The cubic root of 21066452 is about 276.1831207920.

It can be divided in two parts, 2106 and 6452, that added together give a palindrome (8558).

The spelling of 21066452 in words is "twenty-one million, sixty-six thousand, four hundred fifty-two".