100111211212121 has 4 divisors (see below), whose sum is σ = 101143285554612. Its totient is φ = 99079136869632.

The previous prime is 100111211212093. The next prime is 100111211212141. The reversal of 100111211212121 is 121212112111001.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 33826553923600 + 66284657288521 = 5816060^2 + 8141539^2 .

It is a cyclic number.

It is not a de Polignac number, because 100111211212121 - 2⁶ = 100111211212057 is a prime.

It is a super-2 number, since 2×100111211212121² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 100111211212121.

It is not an unprimeable number, because it can be changed into a prime (100111211212141) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 516037171100 + ... + 516037171293.

It is an arithmetic number, because the mean of its divisors is an integer number (25285821388653).

Almost surely, 2^{100111211212121} is an apocalyptic number.

It is an amenable number.

100111211212121 is a deficient number, since it is larger than the sum of its proper divisors (1032074342491).

100111211212121 is an equidigital number, since it uses as much as digits as its factorization.

100111211212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1032074342490.

The product of its (nonzero) digits is 16, while the sum is 17.

Adding to 100111211212121 its reverse (121212112111001), we get a palindrome (221323323323122).

The spelling of 100111211212121 in words is "one hundred trillion, one hundred eleven billion, two hundred eleven million, two hundred twelve thousand, one hundred twenty-one".