201021102100 has 144 divisors (see below), whose sum is σ = 537969040000. Its totient is φ = 63490936320.

The previous prime is 201021102077. The next prime is 201021102101. The reversal of 201021102100 is 1201120102.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201021102101) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4518766 + ... + 4563034.

Almost surely, 2^201021102100 is an apocalyptic number.

201021102100 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 201021102100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (268984520000).

201021102100 is an abundant number, since it is smaller than the sum of its proper divisors (336947937900).

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

201021102100 is a wasteful number, since it uses less digits than its factorization.

201021102100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44802 (or 44795 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 201021102100 its reverse (1201120102), we get a palindrome (202222222202).

The spelling of 201021102100 in words is "two hundred one billion, twenty-one million, one hundred two thousand, one hundred".