100121012100 has 864 divisors, whose sum is σ = 360102951936. Its totient is φ = 23146905600.

The previous prime is 100121012081. The next prime is 100121012111. The reversal of 100121012100 is 1210121001.

It is a happy number.

It is a super-3 number, since 3×100121012100³ (a number of 34 digits) contains 333 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 1410155065 + ... + 1410155135.

It is an arithmetic number, because the mean of its divisors is an integer number (416785824).

Almost surely, 2^100121012100 is an apocalyptic number.

100121012100 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 100121012100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (180051475968).

100121012100 is an abundant number, since it is smaller than the sum of its proper divisors (259981939836).

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

100121012100 is a wasteful number, since it uses less digits than its factorization.

100121012100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245 (or 235 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 100121012100 its reverse (1210121001), we get a palindrome (101331133101).

The spelling of 100121012100 in words is "one hundred billion, one hundred twenty-one million, twelve thousand, one hundred".