21366366 has 32 divisors (see below), whose sum is σ = 49152768. Its totient is φ = 6065280.

The previous prime is 21366343. The next prime is 21366377. The reversal of 21366366 is 66366312.

It is a happy number.

It is a nude number because it is divisible by every one of its digits.

It is a Curzon number.

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 15 ways as a sum of consecutive naturals, for example, 5286 + ... + 8406.

It is an arithmetic number, because the mean of its divisors is an integer number (1536024).

Almost surely, 2^21366366 is an apocalyptic number.

21366366 is an abundant number, since it is smaller than the sum of its proper divisors (27786402).

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

21366366 is a wasteful number, since it uses less digits than its factorization.

21366366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3296.

The product of its digits is 23328, while the sum is 33.

The square root of 21366366 is about 4622.3766614156. The cubic root of 21366366 is about 277.4875832444.

The spelling of 21366366 in words is "twenty-one million, three hundred sixty-six thousand, three hundred sixty-six".