21186066 has 32 divisors (see below), whose sum is σ = 47822400. Its totient is φ = 6198080.

The previous prime is 21186041. The next prime is 21186071. The reversal of 21186066 is 66068112.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3621 + ... + 7448.

It is an arithmetic number, because the mean of its divisors is an integer number (1494450).

Almost surely, 2^21186066 is an apocalyptic number.

21186066 is an abundant number, since it is smaller than the sum of its proper divisors (26636334).

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

21186066 is a wasteful number, since it uses less digits than its factorization.

21186066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11114.

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 21186066 is about 4602.8323888667. The cubic root of 21186066 is about 276.7048514255.

The spelling of 21186066 in words is "twenty-one million, one hundred eighty-six thousand, sixty-six".