221020222001 has 4 divisors (see below), whose sum is σ = 221021783652. Its totient is φ = 221018660352.

The previous prime is 221020221943. The next prime is 221020222021. The reversal of 221020222001 is 100222020122.

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 166301655601 + 54718566400 = 407801^2 + 233920^2 .

It is a cyclic number.

It is not a de Polignac number, because 221020222001 - 2³⁴ = 203840352817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221020222021) 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, 544736 + ... + 859521.

It is an arithmetic number, because the mean of its divisors is an integer number (55255445913).

Almost surely, 2^221020222001 is an apocalyptic number.

It is an amenable number.

221020222001 is a deficient number, since it is larger than the sum of its proper divisors (1561651).

221020222001 is a wasteful number, since it uses less digits than its factorization.

221020222001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1561650.

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 221020222001 its reverse (100222020122), we get a palindrome (321242242123).

The spelling of 221020222001 in words is "two hundred twenty-one billion, twenty million, two hundred twenty-two thousand, one".