100312121021 has 4 divisors (see below), whose sum is σ = 114642424032. Its totient is φ = 85981818012.

The previous prime is 100312120973. The next prime is 100312121057. The reversal of 100312121021 is 120121213001.

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, and also an emirpimes, since its reverse is a distinct semiprime: 120121213001 = 49711 ⋅2416391.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-100312121021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 100312120987 and 100312121005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100311121021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7165151495 + ... + 7165151508.

It is an arithmetic number, because the mean of its divisors is an integer number (28660606008).

Almost surely, 2^100312121021 is an apocalyptic number.

It is an amenable number.

100312121021 is a deficient number, since it is larger than the sum of its proper divisors (14330303011).

100312121021 is an equidigital number, since it uses as much as digits as its factorization.

100312121021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14330303010.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 100312121021 its reverse (120121213001), we get a palindrome (220433334022).

The spelling of 100312121021 in words is "one hundred billion, three hundred twelve million, one hundred twenty-one thousand, twenty-one".