212020121021 has 4 divisors (see below), whose sum is σ = 213289702752. Its totient is φ = 210750539292.

The previous prime is 212020121009. The next prime is 212020121077. The reversal of 212020121021 is 120121020212.

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 a de Polignac number, because none of the positive numbers 2^k-212020121021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212020120987 and 212020121005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212020121921) 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, 634790615 + ... + 634790948.

It is an arithmetic number, because the mean of its divisors is an integer number (53322425688).

Almost surely, 2^212020121021 is an apocalyptic number.

It is an amenable number.

212020121021 is a deficient number, since it is larger than the sum of its proper divisors (1269581731).

212020121021 is a wasteful number, since it uses less digits than its factorization.

212020121021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1269581730.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 212020121021 its reverse (120121020212), we get a palindrome (332141141233).

The spelling of 212020121021 in words is "two hundred twelve billion, twenty million, one hundred twenty-one thousand, twenty-one".