21200020002 has 40 divisors (see below), whose sum is σ = 54290001216. Its totient is φ = 6057148248.

The previous prime is 21200019961. The next prime is 21200020021. The reversal of 21200020002 is 20002000212.

It is a Harshad number since it is a multiple of its sum of digits (9).

21200020002 is a modest number, since divided by 20002 gives 212 as remainder.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 9346318 + ... + 9348585.

Almost surely, 2^21200020002 is an apocalyptic number.

21200020002 is an abundant number, since it is smaller than the sum of its proper divisors (33089981214).

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

21200020002 is a wasteful number, since it uses less digits than its factorization.

21200020002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18694924 (or 18694915 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

Adding to 21200020002 its reverse (20002000212), we get a palindrome (41202020214).

The spelling of 21200020002 in words is "twenty-one billion, two hundred million, twenty thousand, two".