21066446 has 8 divisors (see below), whose sum is σ = 31794024. Its totient is φ = 10468440.

The previous prime is 21066443. The next prime is 21066449. The reversal of 21066446 is 64466012.

It is an interprime number because it is at equal distance from previous prime (21066443) and next prime (21066449).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21066443) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31985 + ... + 32636.

It is an arithmetic number, because the mean of its divisors is an integer number (3974253).

Almost surely, 2^21066446 is an apocalyptic number.

21066446 is a deficient number, since it is larger than the sum of its proper divisors (10727578).

21066446 is a wasteful number, since it uses less digits than its factorization.

21066446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64786.

The product of its (nonzero) digits is 6912, while the sum is 29.

The square root of 21066446 is about 4589.8198221717. The cubic root of 21066446 is about 276.1830945718.

It can be divided in two parts, 21066 and 446, that added together give a palindrome (21512).

The spelling of 21066446 in words is "twenty-one million, sixty-six thousand, four hundred forty-six".