21001222222001 has 8 divisors (see below), whose sum is σ = 24003866436480. Its totient is φ = 17999195410368.

The previous prime is 21001222221989. The next prime is 21001222222069. The reversal of 21001222222001 is 10022222210012.

It is a happy number.

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 21001222222001 - 2³⁸ = 20726344315057 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21001222222091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 154277816 + ... + 154413881.

It is an arithmetic number, because the mean of its divisors is an integer number (3000483304560).

Almost surely, 2^{21001222222001} is an apocalyptic number.

It is an amenable number.

21001222222001 is a deficient number, since it is larger than the sum of its proper divisors (3002644214479).

21001222222001 is an equidigital number, since it uses as much as digits as its factorization.

21001222222001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 308701423.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21001222222001 its reverse (10022222210012), we get a palindrome (31023444432013).

The spelling of 21001222222001 in words is "twenty-one trillion, one billion, two hundred twenty-two million, two hundred twenty-two thousand, one".