212121000122021 has 4 divisors (see below), whose sum is σ = 212121140860044. Its totient is φ = 212120859384000.

The previous prime is 212121000122011. The next prime is 212121000122051. The reversal of 212121000122021 is 120221000121212.

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 107377033319521 + 104743966802500 = 10362289^2 + 10234450^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212121000122021 is a prime.

It is a super-3 number, since 3×212121000122021³ (a number of 44 digits) contains 333 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212121000122011) 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, 68083460 + ... + 71130861.

It is an arithmetic number, because the mean of its divisors is an integer number (53030285215011).

Almost surely, 2^{212121000122021} is an apocalyptic number.

It is an amenable number.

212121000122021 is a deficient number, since it is larger than the sum of its proper divisors (140738023).

212121000122021 is a wasteful number, since it uses less digits than its factorization.

212121000122021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140738022.

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

Adding to 212121000122021 its reverse (120221000121212), we get a palindrome (332342000243233).

The spelling of 212121000122021 in words is "two hundred twelve trillion, one hundred twenty-one billion, one hundred twenty-two thousand, twenty-one".