21220544442611 has 8 divisors (see below), whose sum is σ = 21350270869200. Its totient is φ = 21090955223520.

The previous prime is 21220544442571. The next prime is 21220544442667. The reversal of 21220544442611 is 11624444502212.

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 21220544442611 - 2¹⁸ = 21220544180467 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21220544412611) 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, 33991601 + ... + 34610258.

It is an arithmetic number, because the mean of its divisors is an integer number (2668783858650).

Almost surely, 2^{21220544442611} is an apocalyptic number.

21220544442611 is a deficient number, since it is larger than the sum of its proper divisors (129726426589).

21220544442611 is a wasteful number, since it uses less digits than its factorization.

21220544442611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68603749.

The product of its (nonzero) digits is 122880, while the sum is 38.

Adding to 21220544442611 its reverse (11624444502212), we get a palindrome (32844988944823).

The spelling of 21220544442611 in words is "twenty-one trillion, two hundred twenty billion, five hundred forty-four million, four hundred forty-two thousand, six hundred eleven".