100021100121 has 6 divisors (see below), whose sum is σ = 144474922410. Its totient is φ = 66680733408.

The previous prime is 100021100117. The next prime is 100021100173. The reversal of 100021100121 is 121001120001.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 99626084496 + 395015625 = 315636^2 + 19875^2 .

It is not a de Polignac number, because 100021100121 - 2² = 100021100117 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 11113455569 = 100021100121 / (1 + 0 + 0 + 0 + 2 + 1 + 1 + 0 + 0 + 1 + 2 + 1).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (100021100191) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5556727776 + ... + 5556727793.

It is an arithmetic number, because the mean of its divisors is an integer number (24079153735).

Almost surely, 2^100021100121 is an apocalyptic number.

It is an amenable number.

100021100121 is a deficient number, since it is larger than the sum of its proper divisors (44453822289).

100021100121 is a wasteful number, since it uses less digits than its factorization.

100021100121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11113455575 (or 11113455572 counting only the distinct ones).

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

Adding to 100021100121 its reverse (121001120001), we get a palindrome (221022220122).

The spelling of 100021100121 in words is "one hundred billion, twenty-one million, one hundred thousand, one hundred twenty-one".