20975566 has 8 divisors (see below), whose sum is σ = 31495464. Its totient is φ = 10477080.

The previous prime is 20975557. The next prime is 20975567. The reversal of 20975566 is 66557902.

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 (20975567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2625 + ... + 6988.

It is an arithmetic number, because the mean of its divisors is an integer number (3936933).

Almost surely, 2^20975566 is an apocalyptic number.

20975566 is a deficient number, since it is larger than the sum of its proper divisors (10519898).

20975566 is a wasteful number, since it uses less digits than its factorization.

20975566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10706.

The product of its (nonzero) digits is 113400, while the sum is 40.

The square root of 20975566 is about 4579.9089510601. The cubic root of 20975566 is about 275.7853736457.

The spelling of 20975566 in words is "twenty million, nine hundred seventy-five thousand, five hundred sixty-six".