212121100210021 has 8 divisors (see below), whose sum is σ = 212557620623360. Its totient is φ = 211684583705328.

The previous prime is 212121100210009. The next prime is 212121100210031. The reversal of 212121100210021 is 120012001121212.

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 212121100210021 - 2²³ = 212121091821413 is a prime.

It is a super-3 number, since 3×212121100210021³ (a number of 44 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212121100209977 and 212121100210004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212121100210031) 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, 124134595 + ... + 125831791.

It is an arithmetic number, because the mean of its divisors is an integer number (26569702577920).

Almost surely, 2^{212121100210021} is an apocalyptic number.

It is an amenable number.

212121100210021 is a deficient number, since it is larger than the sum of its proper divisors (436520413339).

212121100210021 is a wasteful number, since it uses less digits than its factorization.

212121100210021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1954323.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 212121100210021 its reverse (120012001121212), we get a palindrome (332133101331233).

The spelling of 212121100210021 in words is "two hundred twelve trillion, one hundred twenty-one billion, one hundred million, two hundred ten thousand, twenty-one".