21364786 has 8 divisors (see below), whose sum is σ = 32189040. Its totient is φ = 10635108.

The previous prime is 21364771. The next prime is 21364807. The reversal of 21364786 is 68746312.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23076 + ... + 23983.

It is an arithmetic number, because the mean of its divisors is an integer number (4023630).

Almost surely, 2^21364786 is an apocalyptic number.

21364786 is a deficient number, since it is larger than the sum of its proper divisors (10824254).

21364786 is a wasteful number, since it uses less digits than its factorization.

21364786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47288.

The product of its digits is 48384, while the sum is 37.

The square root of 21364786 is about 4622.2057505048. The cubic root of 21364786 is about 277.4807431920.

The spelling of 21364786 in words is "twenty-one million, three hundred sixty-four thousand, seven hundred eighty-six".