21894766 has 4 divisors (see below), whose sum is σ = 32842152. Its totient is φ = 10947382.

The previous prime is 21894751. The next prime is 21894839. The reversal of 21894766 is 66749812.

It is a semiprime because it is the product of two primes.

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 as a sum of consecutive naturals, namely, 5473690 + ... + 5473693.

It is an arithmetic number, because the mean of its divisors is an integer number (8210538).

Almost surely, 2^21894766 is an apocalyptic number.

21894766 is a deficient number, since it is larger than the sum of its proper divisors (10947386).

21894766 is a wasteful number, since it uses less digits than its factorization.

21894766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10947385.

The product of its digits is 145152, while the sum is 43.

The square root of 21894766 is about 4679.1843306286. The cubic root of 21894766 is about 279.7564463734.

The spelling of 21894766 in words is "twenty-one million, eight hundred ninety-four thousand, seven hundred sixty-six".