21066633 has 24 divisors (see below), whose sum is σ = 35063808. Its totient is φ = 11938752.

The previous prime is 21066613. The next prime is 21066641. The reversal of 21066633 is 33666012.

It is not a de Polignac number, because 21066633 - 2⁵ = 21066601 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21066597 and 21066606.

It is not an unprimeable number, because it can be changed into a prime (21066613) 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 23 ways as a sum of consecutive naturals, for example, 6685 + ... + 9317.

It is an arithmetic number, because the mean of its divisors is an integer number (1460992).

Almost surely, 2^21066633 is an apocalyptic number.

It is an amenable number.

21066633 is a deficient number, since it is larger than the sum of its proper divisors (13997175).

21066633 is a wasteful number, since it uses less digits than its factorization.

21066633 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2773 (or 2770 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 27.

The square root of 21066633 is about 4589.8401932965. The cubic root of 21066633 is about 276.1839117653.

The spelling of 21066633 in words is "twenty-one million, sixty-six thousand, six hundred thirty-three".