20101121222221 has 8 divisors (see below), whose sum is σ = 21682675127960. Its totient is φ = 18524612146752.

The previous prime is 20101121222209. The next prime is 20101121222251. The reversal of 20101121222221 is 12222212110102.

It can be written as a sum of positive squares in 4 ways, for example, as 353638355625 + 19747482866596 = 594675^2 + 4443814^2 .

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 20101121222221 - 2¹⁵ = 20101121189453 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20101121222251) 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, 1261199286 + ... + 1261215223.

It is an arithmetic number, because the mean of its divisors is an integer number (2710334390995).

Almost surely, 2^{20101121222221} is an apocalyptic number.

It is an amenable number.

20101121222221 is a deficient number, since it is larger than the sum of its proper divisors (1581553905739).

20101121222221 is a wasteful number, since it uses less digits than its factorization.

20101121222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2522415135.

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

Adding to 20101121222221 its reverse (12222212110102), we get a palindrome (32323333332323).

The spelling of 20101121222221 in words is "twenty trillion, one hundred one billion, one hundred twenty-one million, two hundred twenty-two thousand, two hundred twenty-one".