2101222212121 has 8 divisors (see below), whose sum is σ = 2175220902600. Its totient is φ = 2027326371840.

The previous prime is 2101222212097. The next prime is 2101222212139. The reversal of 2101222212121 is 1212122221012.

It can be written as a sum of positive squares in 4 ways, for example, as 350033156496 + 1751189055625 = 591636^2 + 1323325^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2101222212121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2101222212151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25670970 + ... + 25752691.

It is an arithmetic number, because the mean of its divisors is an integer number (271902612825).

Almost surely, 2^{2101222212121} is an apocalyptic number.

It is an amenable number.

2101222212121 is a deficient number, since it is larger than the sum of its proper divisors (73998690479).

2101222212121 is a wasteful number, since it uses less digits than its factorization.

2101222212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51425099.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 2101222212121 its reverse (1212122221012), we get a palindrome (3313344433133).

The spelling of 2101222212121 in words is "two trillion, one hundred one billion, two hundred twenty-two million, two hundred twelve thousand, one hundred twenty-one".