20569966 has 16 divisors (see below), whose sum is σ = 32828544. Its totient is φ = 9633024.

The previous prime is 20569933. The next prime is 20569999. The reversal of 20569966 is 66996502.

It is an interprime number because it is at equal distance from previous prime (20569933) and next prime (20569999).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6226 + ... + 8938.

It is an arithmetic number, because the mean of its divisors is an integer number (2051784).

Almost surely, 2^20569966 is an apocalyptic number.

20569966 is a deficient number, since it is larger than the sum of its proper divisors (12258578).

20569966 is a wasteful number, since it uses less digits than its factorization.

20569966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2955.

The product of its (nonzero) digits is 174960, while the sum is 43.

The square root of 20569966 is about 4535.4124399000. The cubic root of 20569966 is about 273.9961904740.

The spelling of 20569966 in words is "twenty million, five hundred sixty-nine thousand, nine hundred sixty-six".