210000021100 has 72 divisors (see below), whose sum is σ = 476284515840. Its totient is φ = 80217487680.

The previous prime is 210000021083. The next prime is 210000021107. The reversal of 210000021100 is 1120000012.

It is not an unprimeable number, because it can be changed into a prime (210000021107) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1349949 + ... + 1497451.

It is an arithmetic number, because the mean of its divisors is an integer number (6615062720).

Almost surely, 2^210000021100 is an apocalyptic number.

210000021100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 210000021100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (238142257920).

210000021100 is an abundant number, since it is smaller than the sum of its proper divisors (266284494740).

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

210000021100 is a wasteful number, since it uses less digits than its factorization.

210000021100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148159 (or 148152 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 7.

Adding to 210000021100 its reverse (1120000012), we get a palindrome (211120021112).

The spelling of 210000021100 in words is "two hundred ten billion, twenty-one thousand, one hundred".