12101020021 has 4 divisors (see below), whose sum is σ = 12107948512. Its totient is φ = 12094091532.

The previous prime is 12101019977. The next prime is 12101020027. The reversal of 12101020021 is 12002010121.

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: 12002010121 = 23 ⋅521826527.

It is a cyclic number.

It is not a de Polignac number, because 12101020021 - 2¹³ = 12101011829 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12101020027) 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, 3461625 + ... + 3465118.

It is an arithmetic number, because the mean of its divisors is an integer number (3026987128).

Almost surely, 2^12101020021 is an apocalyptic number.

It is an amenable number.

12101020021 is a deficient number, since it is larger than the sum of its proper divisors (6928491).

12101020021 is an equidigital number, since it uses as much as digits as its factorization.

12101020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6928490.

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

Adding to 12101020021 its reverse (12002010121), we get a palindrome (24103030142).

The spelling of 12101020021 in words is "twelve billion, one hundred one million, twenty thousand, twenty-one".