20566906873 has 4 divisors (see below), whose sum is σ = 20568643200. Its totient is φ = 20565170548.

The previous prime is 20566906813. The next prime is 20566906883. The reversal of 20566906873 is 37860966502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20566906873 is a prime.

It is a super-3 number, since 3×20566906873³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20566906873.

It is not an unprimeable number, because it can be changed into a prime (20566906813) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 850273 + ... + 874126.

It is an arithmetic number, because the mean of its divisors is an integer number (5142160800).

Almost surely, 2^20566906873 is an apocalyptic number.

It is an amenable number.

20566906873 is a deficient number, since it is larger than the sum of its proper divisors (1736327).

20566906873 is a wasteful number, since it uses less digits than its factorization.

20566906873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1736326.

The product of its (nonzero) digits is 3265920, while the sum is 52.

The spelling of 20566906873 in words is "twenty billion, five hundred sixty-six million, nine hundred six thousand, eight hundred seventy-three".