212120121002021 has 4 divisors (see below), whose sum is σ = 212127352481292. Its totient is φ = 212112889522752.

The previous prime is 212120121002011. The next prime is 212120121002057. The reversal of 212120121002021 is 120200121021212.

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 194564976309025 + 17555144692996 = 13948655^2 + 4189886^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212120121002021 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 (212120121002011) 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, 3615695636 + ... + 3615754301.

It is an arithmetic number, because the mean of its divisors is an integer number (53031838120323).

Almost surely, 2^{212120121002021} is an apocalyptic number.

It is an amenable number.

212120121002021 is a deficient number, since it is larger than the sum of its proper divisors (7231479271).

212120121002021 is an equidigital number, since it uses as much as digits as its factorization.

212120121002021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7231479270.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 212120121002021 its reverse (120200121021212), we get a palindrome (332320242023233).

The spelling of 212120121002021 in words is "two hundred twelve trillion, one hundred twenty billion, one hundred twenty-one million, two thousand, twenty-one".