100131212121 has 4 divisors (see below), whose sum is σ = 133508282832. Its totient is φ = 66754141412.

The previous prime is 100131212119. The next prime is 100131212179. The reversal of 100131212121 is 121212131001.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 100131212121 - 2¹ = 100131212119 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 100131212121.

It is not an unprimeable number, because it can be changed into a prime (100131211121) 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, 16688535351 + ... + 16688535356.

It is an arithmetic number, because the mean of its divisors is an integer number (33377070708).

Almost surely, 2^100131212121 is an apocalyptic number.

It is an amenable number.

100131212121 is a deficient number, since it is larger than the sum of its proper divisors (33377070711).

100131212121 is an equidigital number, since it uses as much as digits as its factorization.

100131212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33377070710.

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 100131212121 its reverse (121212131001), we get a palindrome (221343343122).

The spelling of 100131212121 in words is "one hundred billion, one hundred thirty-one million, two hundred twelve thousand, one hundred twenty-one".