21412766 has 4 divisors (see below), whose sum is σ = 32119152. Its totient is φ = 10706382.

The previous prime is 21412739. The next prime is 21412789. The reversal of 21412766 is 66721412.

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 polite number, since it can be written as a sum of consecutive naturals, namely, 5353190 + ... + 5353193.

It is an arithmetic number, because the mean of its divisors is an integer number (8029788).

Almost surely, 2^21412766 is an apocalyptic number.

21412766 is a deficient number, since it is larger than the sum of its proper divisors (10706386).

21412766 is a wasteful number, since it uses less digits than its factorization.

21412766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10706385.

The product of its digits is 4032, while the sum is 29.

The square root of 21412766 is about 4627.3930025447. The cubic root of 21412766 is about 277.6883054892.

The spelling of 21412766 in words is "twenty-one million, four hundred twelve thousand, seven hundred sixty-six".