20010122222221 has 4 divisors (see below), whose sum is σ = 20010344644444. Its totient is φ = 20009899800000.

The previous prime is 20010122222213. The next prime is 20010122222263. The reversal of 20010122222221 is 12222222101002.

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 14205443918121 + 5804678304100 = 3769011^2 + 2409290^2 .

It is a cyclic number.

It is not a de Polignac number, because 20010122222221 - 2³ = 20010122222213 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 (20010122222201) 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, 111076110 + ... + 111256111.

It is an arithmetic number, because the mean of its divisors is an integer number (5002586161111).

Almost surely, 2^{20010122222221} is an apocalyptic number.

It is an amenable number.

20010122222221 is a deficient number, since it is larger than the sum of its proper divisors (222422223).

20010122222221 is an equidigital number, since it uses as much as digits as its factorization.

20010122222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222422222.

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 20010122222221 its reverse (12222222101002), we get a palindrome (32232344323223).

The spelling of 20010122222221 in words is "twenty trillion, ten billion, one hundred twenty-two million, two hundred twenty-two thousand, two hundred twenty-one".