21011366 has 8 divisors (see below), whose sum is σ = 32533824. Its totient is φ = 10166760.

The previous prime is 21011357. The next prime is 21011383. The reversal of 21011366 is 66311012.

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

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 169385 + ... + 169508.

It is an arithmetic number, because the mean of its divisors is an integer number (4066728).

Almost surely, 2^21011366 is an apocalyptic number.

21011366 is a deficient number, since it is larger than the sum of its proper divisors (11522458).

21011366 is a wasteful number, since it uses less digits than its factorization.

21011366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 338926.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 21011366 is about 4583.8156594697. The cubic root of 21011366 is about 275.9421831564.

Adding to 21011366 its reverse (66311012), we get a palindrome (87322378).

The spelling of 21011366 in words is "twenty-one million, eleven thousand, three hundred sixty-six".