21021020200 has 96 divisors (see below), whose sum is σ = 53998954560. Its totient is φ = 7569689600.

The previous prime is 21021020161. The next prime is 21021020239. The reversal of 21021020200 is 202012012.

It is an interprime number because it is at equal distance from previous prime (21021020161) and next prime (21021020239).

It is a Harshad number since it is a multiple of its sum of digits (10).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 56206 + ... + 212605.

It is an arithmetic number, because the mean of its divisors is an integer number (562489110).

Almost surely, 2^21021020200 is an apocalyptic number.

21021020200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21021020200 is an abundant number, since it is smaller than the sum of its proper divisors (32977934360).

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

21021020200 is a wasteful number, since it uses less digits than its factorization.

21021020200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268867 (or 268858 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 21021020200 its reverse (202012012), we get a palindrome (21223032212).

The spelling of 21021020200 in words is "twenty-one billion, twenty-one million, twenty thousand, two hundred".