21432066 has 16 divisors (see below), whose sum is σ = 42985344. Its totient is φ = 7123824.

The previous prime is 21432023. The next prime is 21432077. The reversal of 21432066 is 66023412.

It is a super-3 number, since 3×21432066³ (a number of 23 digits) contains 333 as substring.

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, 2665 + ... + 7068.

It is an arithmetic number, because the mean of its divisors is an integer number (2686584).

Almost surely, 2^21432066 is an apocalyptic number.

21432066 is an abundant number, since it is smaller than the sum of its proper divisors (21553278).

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

21432066 is a wasteful number, since it uses less digits than its factorization.

21432066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10105.

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 21432066 is about 4629.4779403298. The cubic root of 21432066 is about 277.7717101726.

Adding to 21432066 its reverse (66023412), we get a palindrome (87455478).

The spelling of 21432066 in words is "twenty-one million, four hundred thirty-two thousand, sixty-six".