2021102100 has 108 divisors (see below), whose sum is σ = 6344711100. Its totient is φ = 538137600.

The previous prime is 2021102099. The next prime is 2021102123. The reversal of 2021102100 is 12011202.

It can be written as a sum of positive squares in 6 ways, for example, as 8503056 + 2012599044 = 2916^2 + 44862^2 .

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 35 ways as a sum of consecutive naturals, for example, 791626 + ... + 794174.

It is an arithmetic number, because the mean of its divisors is an integer number (58747325).

Almost surely, 2^2021102100 is an apocalyptic number.

2021102100 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 2021102100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3172355550).

2021102100 is an abundant number, since it is smaller than the sum of its proper divisors (4323609000).

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

2021102100 is a wasteful number, since it uses less digits than its factorization.

2021102100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3450 (or 3440 counting only the distinct ones).

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

The square root of 2021102100 is about 44956.6691381824. The cubic root of 2021102100 is about 1264.3367194645.

Adding to 2021102100 its reverse (12011202), we get a palindrome (2033113302).

It can be divided in two parts, 2021102 and 100, that added together give a palindrome (2021202).

The spelling of 2021102100 in words is "two billion, twenty-one million, one hundred two thousand, one hundred".