21716212020 has 48 divisors (see below), whose sum is σ = 60834715200. Its totient is φ = 5788197376.

The previous prime is 21716212009. The next prime is 21716212043. The reversal of 21716212020 is 2021261712.

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, 39724 + ... + 212156.

It is an arithmetic number, because the mean of its divisors is an integer number (1267389900).

Almost surely, 2^21716212020 is an apocalyptic number.

21716212020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21716212020 is an abundant number, since it is smaller than the sum of its proper divisors (39118503180).

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

21716212020 is a wasteful number, since it uses less digits than its factorization.

21716212020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174544 (or 174542 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 24.

Adding to 21716212020 its reverse (2021261712), we get a palindrome (23737473732).

The spelling of 21716212020 in words is "twenty-one billion, seven hundred sixteen million, two hundred twelve thousand, twenty".