20520018887 has 4 divisors (see below), whose sum is σ = 20525609280. Its totient is φ = 20514428496.

The previous prime is 20520018833. The next prime is 20520018899. The reversal of 20520018887 is 78881002502.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20520018887 - 2⁶ = 20520018823 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20520018817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2789687 + ... + 2797032.

It is an arithmetic number, because the mean of its divisors is an integer number (5131402320).

Almost surely, 2^20520018887 is an apocalyptic number.

20520018887 is a deficient number, since it is larger than the sum of its proper divisors (5590393).

20520018887 is an equidigital number, since it uses as much as digits as its factorization.

20520018887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5590392.

The product of its (nonzero) digits is 71680, while the sum is 41.

The spelling of 20520018887 in words is "twenty billion, five hundred twenty million, eighteen thousand, eight hundred eighty-seven".