21221212101001 has 32 divisors (see below), whose sum is σ = 23591591521920. Its totient is φ = 18927898752000.

The previous prime is 21221212100989. The next prime is 21221212101049. The reversal of 21221212101001 is 10010121212212.

It is a cyclic number.

It is not a de Polignac number, because 21221212101001 - 2¹¹ = 21221212098953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21221212101071) 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 31 ways as a sum of consecutive naturals, for example, 688336855 + ... + 688367683.

It is an arithmetic number, because the mean of its divisors is an integer number (737237235060).

Almost surely, 2^{21221212101001} is an apocalyptic number.

It is an amenable number.

21221212101001 is a deficient number, since it is larger than the sum of its proper divisors (2370379420919).

21221212101001 is a wasteful number, since it uses less digits than its factorization.

21221212101001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36537.

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

Adding to 21221212101001 its reverse (10010121212212), we get a palindrome (31231333313213).

The spelling of 21221212101001 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twelve million, one hundred one thousand, one".