1001002100 has 72 divisors (see below), whose sum is σ = 2490132288. Its totient is φ = 342144000.

The previous prime is 1001002069. The next prime is 1001002111. The reversal of 1001002100 is 12001001.

It is a happy number.

1001002100 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (5).

It is a congruent number.

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, 245075 + ... + 249125.

Almost surely, 2^1001002100 is an apocalyptic number.

1001002100 is a gapful number since it is divisible by the number (10) 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 1001002100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1245066144).

1001002100 is an abundant number, since it is smaller than the sum of its proper divisors (1489130188).

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

1001002100 is a wasteful number, since it uses less digits than its factorization.

1001002100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4425 (or 4418 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 5.

The square root of 1001002100 is about 31638.6172264213. The cubic root of 1001002100 is about 1000.3339218171. Note that the first 3 decimals are identical.

Adding to 1001002100 its reverse (12001001), we get a palindrome (1013003101).

The spelling of 1001002100 in words is "one billion, one million, two thousand, one hundred".