2021212202021 has 4 divisors (see below), whose sum is σ = 2140107037452. Its totient is φ = 1902317366592.

The previous prime is 2021212201951. The next prime is 2021212202027. The reversal of 2021212202021 is 1202022121202.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1400165757796 + 621046444225 = 1183286^2 + 788065^2 .

It is a cyclic number.

It is not a de Polignac number, because 2021212202021 - 2¹⁴ = 2021212185637 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 118894835413 = 2021212202021 / (2 + 0 + 2 + 1 + 2 + 1 + 2 + 2 + 0 + 2 + 0 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2021212202027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 59447417690 + ... + 59447417723.

It is an arithmetic number, because the mean of its divisors is an integer number (535026759363).

Almost surely, 2^{2021212202021} is an apocalyptic number.

It is an amenable number.

2021212202021 is a deficient number, since it is larger than the sum of its proper divisors (118894835431).

2021212202021 is a wasteful number, since it uses less digits than its factorization.

2021212202021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118894835430.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 2021212202021 its reverse (1202022121202), we get a palindrome (3223234323223).

The spelling of 2021212202021 in words is "two trillion, twenty-one billion, two hundred twelve million, two hundred two thousand, twenty-one".