20884770887 has 4 divisors (see below), whose sum is σ = 21005492280. Its totient is φ = 20764049496.

The previous prime is 20884770847. The next prime is 20884770889. The reversal of 20884770887 is 78807748802.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78807748802 = 2 ⋅39403874401.

It is a cyclic number.

It is not a de Polignac number, because 20884770887 - 2²⁸ = 20616335431 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 (20884770889) 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, 60360437 + ... + 60360782.

It is an arithmetic number, because the mean of its divisors is an integer number (5251373070).

Almost surely, 2^20884770887 is an apocalyptic number.

20884770887 is a deficient number, since it is larger than the sum of its proper divisors (120721393).

20884770887 is a wasteful number, since it uses less digits than its factorization.

20884770887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120721392.

The product of its (nonzero) digits is 11239424, while the sum is 59.

The spelling of 20884770887 in words is "twenty billion, eight hundred eighty-four million, seven hundred seventy thousand, eight hundred eighty-seven".