20887173805 has 16 divisors (see below), whose sum is σ = 25557903360. Its totient is φ = 16382397888.

The previous prime is 20887173773. The next prime is 20887173829. The reversal of 20887173805 is 50837178802.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20887173805 - 2⁵ = 20887173773 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15124 + ... + 204946.

It is an arithmetic number, because the mean of its divisors is an integer number (1597368960).

Almost surely, 2^20887173805 is an apocalyptic number.

It is an amenable number.

20887173805 is a deficient number, since it is larger than the sum of its proper divisors (4670729555).

20887173805 is a wasteful number, since it uses less digits than its factorization.

20887173805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190260.

The product of its (nonzero) digits is 752640, while the sum is 49.

The spelling of 20887173805 in words is "twenty billion, eight hundred eighty-seven million, one hundred seventy-three thousand, eight hundred five".