21386366 has 16 divisors (see below), whose sum is σ = 33826464. Its totient is φ = 10120704.

The previous prime is 21386359. The next prime is 21386399. The reversal of 21386366 is 66368312.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2066 + ... + 6858.

It is an arithmetic number, because the mean of its divisors is an integer number (2114154).

Almost surely, 2^21386366 is an apocalyptic number.

21386366 is a deficient number, since it is larger than the sum of its proper divisors (12440098).

21386366 is a wasteful number, since it uses less digits than its factorization.

21386366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4915.

The product of its digits is 31104, while the sum is 35.

The square root of 21386366 is about 4624.5395446466. The cubic root of 21386366 is about 277.5741370513.

The spelling of 21386366 in words is "twenty-one million, three hundred eighty-six thousand, three hundred sixty-six".