10121212021 has 4 divisors (see below), whose sum is σ = 10716577452. Its totient is φ = 9525846592.

The previous prime is 10121212001. The next prime is 10121212051. The reversal of 10121212021 is 12021212101.

10121212021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12021212101 = 8291 ⋅1449911.

It can be written as a sum of positive squares in 2 ways, for example, as 8780627025 + 1340584996 = 93705^2 + 36614^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-10121212021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 10121211992 and 10121212010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10121212001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 297682690 + ... + 297682723.

It is an arithmetic number, because the mean of its divisors is an integer number (2679144363).

Almost surely, 2^10121212021 is an apocalyptic number.

It is an amenable number.

10121212021 is a deficient number, since it is larger than the sum of its proper divisors (595365431).

10121212021 is an equidigital number, since it uses as much as digits as its factorization.

10121212021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 595365430.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 10121212021 its reverse (12021212101), we get a palindrome (22142424122).

The spelling of 10121212021 in words is "ten billion, one hundred twenty-one million, two hundred twelve thousand, twenty-one".