2101220100 has 216 divisors, whose sum is σ = 7655968320. Its totient is φ = 472055040.

The previous prime is 2101220087. The next prime is 2101220167. The reversal of 2101220100 is 10221012.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 368874 + ... + 374526.

Almost surely, 2^2101220100 is an apocalyptic number.

2101220100 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 2101220100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3827984160).

2101220100 is an abundant number, since it is smaller than the sum of its proper divisors (5554748220).

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

2101220100 is a wasteful number, since it uses less digits than its factorization.

2101220100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5739 (or 5729 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 2101220100 is about 45839.0673988902. The cubic root of 2101220100 is about 1280.8271224709.

Adding to 2101220100 its reverse (10221012), we get a palindrome (2111441112).

The spelling of 2101220100 in words is "two billion, one hundred one million, two hundred twenty thousand, one hundred".