21202066 has 16 divisors (see below), whose sum is σ = 32327064. Its totient is φ = 10427904.

The previous prime is 21202039. The next prime is 21202079. The reversal of 21202066 is 66020212.

It can be written as a sum of positive squares in 4 ways, for example, as 20894041 + 308025 = 4571^2 + 555^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56656 + ... + 57028.

Almost surely, 2^21202066 is an apocalyptic number.

21202066 is a deficient number, since it is larger than the sum of its proper divisors (11124998).

21202066 is a wasteful number, since it uses less digits than its factorization.

21202066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 765.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 21202066 is about 4604.5701210862. The cubic root of 21202066 is about 276.7744909640.

Adding to 21202066 its reverse (66020212), we get a palindrome (87222278).

It can be divided in two parts, 2120206 and 6, that added together give a palindrome (2120212).

The spelling of 21202066 in words is "twenty-one million, two hundred two thousand, sixty-six".