21986820020 has 24 divisors (see below), whose sum is σ = 50369806368. Its totient is φ = 7995207200.

The previous prime is 21986819999. The next prime is 21986820041. The reversal of 21986820020 is 2002868912.

It is an interprime number because it is at equal distance from previous prime (21986819999) and next prime (21986820041).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49969826 + ... + 49970265.

It is an arithmetic number, because the mean of its divisors is an integer number (2098741932).

Almost surely, 2^21986820020 is an apocalyptic number.

21986820020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21986820020 is an abundant number, since it is smaller than the sum of its proper divisors (28382986348).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21986820020 is a wasteful number, since it uses less digits than its factorization.

21986820020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99940111 (or 99940109 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 38.

The spelling of 21986820020 in words is "twenty-one billion, nine hundred eighty-six million, eight hundred twenty thousand, twenty".