21002266 has 8 divisors (see below), whose sum is σ = 32873184. Its totient is φ = 10044540.

The previous prime is 21002251. The next prime is 21002269. The reversal of 21002266 is 66220012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21002269) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 228240 + ... + 228331.

It is an arithmetic number, because the mean of its divisors is an integer number (4109148).

Almost surely, 2^21002266 is an apocalyptic number.

21002266 is a deficient number, since it is larger than the sum of its proper divisors (11870918).

21002266 is a wasteful number, since it uses less digits than its factorization.

21002266 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 456596.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 21002266 is about 4582.8229291562. The cubic root of 21002266 is about 275.9023406498.

Adding to 21002266 its reverse (66220012), we get a palindrome (87222278).

The spelling of 21002266 in words is "twenty-one million, two thousand, two hundred sixty-six".