221001000101001 has 16 divisors (see below), whose sum is σ = 327437367265600. Its totient is φ = 147321184865184.

The previous prime is 221001000100999. The next prime is 221001000101171. The reversal of 221001000101001 is 100101000100122.

It is a happy number.

It is not a de Polignac number, because 221001000101001 - 2¹ = 221001000100999 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221001000101201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 355661671 + ... + 356282508.

It is an arithmetic number, because the mean of its divisors is an integer number (20464835454100).

Almost surely, 2^{221001000101001} is an apocalyptic number.

It is an amenable number.

221001000101001 is a deficient number, since it is larger than the sum of its proper divisors (106436367164599).

221001000101001 is a wasteful number, since it uses less digits than its factorization.

221001000101001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 711955685 (or 711955679 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 221001000101001 its reverse (100101000100122), we get a palindrome (321102000201123).

The spelling of 221001000101001 in words is "two hundred twenty-one trillion, one billion, one hundred one thousand, one".