212121211122021 has 8 divisors (see below), whose sum is σ = 292580980858080. Its totient is φ = 136537791066992.

The previous prime is 212121211122017. The next prime is 212121211122043. The reversal of 212121211122021 is 120221112121212.

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 212121211122021 - 2² = 212121211122017 is a prime.

It is a super-2 number, since 2×212121211122021² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212121211123021) 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, 1219087420155 + ... + 1219087420328.

It is an arithmetic number, because the mean of its divisors is an integer number (36572622607260).

Almost surely, 2^{212121211122021} is an apocalyptic number.

It is an amenable number.

212121211122021 is a deficient number, since it is larger than the sum of its proper divisors (80459769736059).

212121211122021 is a wasteful number, since it uses less digits than its factorization.

212121211122021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2438174840515.

The product of its (nonzero) digits is 128, while the sum is 21.

Adding to 212121211122021 its reverse (120221112121212), we get a palindrome (332342323243233).

The spelling of 212121211122021 in words is "two hundred twelve trillion, one hundred twenty-one billion, two hundred eleven million, one hundred twenty-two thousand, twenty-one".