10121200021 has 4 divisors (see below), whose sum is σ = 10122518272. Its totient is φ = 10119881772.

The previous prime is 10121199997. The next prime is 10121200031. The reversal of 10121200021 is 12000212101.

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 10121200021 - 2⁵ = 10121199989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 10121199980 and 10121200007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10121200031) 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, 647541 + ... + 662986.

It is an arithmetic number, because the mean of its divisors is an integer number (2530629568).

Almost surely, 2^10121200021 is an apocalyptic number.

It is an amenable number.

10121200021 is a deficient number, since it is larger than the sum of its proper divisors (1318251).

10121200021 is an equidigital number, since it uses as much as digits as its factorization.

10121200021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1318250.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 10121200021 its reverse (12000212101), we get a palindrome (22121412122).

The spelling of 10121200021 in words is "ten billion, one hundred twenty-one million, two hundred thousand, twenty-one".