21000220000 has 60 divisors (see below), whose sum is σ = 51663740436. Its totient is φ = 8400080000.

The previous prime is 21000219983. The next prime is 21000220009. The reversal of 21000220000 is 2200012.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000220009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 505006 + ... + 545005.

Almost surely, 2^21000220000 is an apocalyptic number.

21000220000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21000220000 is an abundant number, since it is smaller than the sum of its proper divisors (30663520436).

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

21000220000 is an equidigital number, since it uses as much as digits as its factorization.

21000220000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1050041 (or 1050018 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 7.

Adding to 21000220000 its reverse (2200012), we get a palindrome (21002420012).

The spelling of 21000220000 in words is "twenty-one billion, two hundred twenty thousand".