12121202020021 has 8 divisors (see below), whose sum is σ = 12539297295000. Its totient is φ = 11703114931200.

The previous prime is 12121202020003. The next prime is 12121202020033. The reversal of 12121202020021 is 12002020212121.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 4194668551921 + 7926533468100 = 2048089^2 + 2815410^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12121202020021 - 2¹⁵ = 12121201987253 is a prime.

It is a super-2 number, since 2×12121202020021² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12121202019977 and 12121202020004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12121202020091) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1045105 + ... + 5033353.

It is an arithmetic number, because the mean of its divisors is an integer number (1567412161875).

Almost surely, 2^{12121202020021} is an apocalyptic number.

It is an amenable number.

12121202020021 is a deficient number, since it is larger than the sum of its proper divisors (418095274979).

12121202020021 is a wasteful number, since it uses less digits than its factorization.

12121202020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4093079.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 12121202020021 its reverse (12002020212121), we get a palindrome (24123222232142).

The spelling of 12121202020021 in words is "twelve trillion, one hundred twenty-one billion, two hundred two million, twenty thousand, twenty-one".