21066674 has 4 divisors (see below), whose sum is σ = 31600014. Its totient is φ = 10533336.

The previous prime is 21066641. The next prime is 21066677. The reversal of 21066674 is 47666012.

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

It can be written as a sum of positive squares in only one way, i.e., 11175649 + 9891025 = 3343^2 + 3145^2 .

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21066674.

It is not an unprimeable number, because it can be changed into a prime (21066677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5266667 + ... + 5266670.

Almost surely, 2^21066674 is an apocalyptic number.

21066674 is a deficient number, since it is larger than the sum of its proper divisors (10533340).

21066674 is a wasteful number, since it uses less digits than its factorization.

21066674 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10533339.

The product of its (nonzero) digits is 12096, while the sum is 32.

The square root of 21066674 is about 4589.8446596808. The cubic root of 21066674 is about 276.1840909354.

The spelling of 21066674 in words is "twenty-one million, sixty-six thousand, six hundred seventy-four".