20020021111987 has 4 divisors (see below), whose sum is σ = 21560022736000. Its totient is φ = 18480019487976.

The previous prime is 20020021111919. The next prime is 20020021111991. The reversal of 20020021111987 is 78911112002002.

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 20020021111987 - 2²³ = 20020012723379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20020021111187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 770000811987 + ... + 770000812012.

It is an arithmetic number, because the mean of its divisors is an integer number (5390005684000).

Almost surely, 2^{20020021111987} is an apocalyptic number.

20020021111987 is a deficient number, since it is larger than the sum of its proper divisors (1540001624013).

20020021111987 is a wasteful number, since it uses less digits than its factorization.

20020021111987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1540001624012.

The product of its (nonzero) digits is 4032, while the sum is 34.

Adding to 20020021111987 its reverse (78911112002002), we get a palindrome (98931133113989).

The spelling of 20020021111987 in words is "twenty trillion, twenty billion, twenty-one million, one hundred eleven thousand, nine hundred eighty-seven".