1622220201721 has 6 divisors (see below), whose sum is σ = 1887072479610. Its totient is φ = 1390474458576.

The previous prime is 1622220201713. The next prime is 1622220201743. The reversal of 1622220201721 is 1271020222261.

It can be written as a sum of positive squares in only one way, i.e., 1021999683600 + 600220518121 = 1010940^2 + 774739^2 .

It is not a de Polignac number, because 1622220201721 - 2³ = 1622220201713 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1622220201721.

It is not an unprimeable number, because it can be changed into a prime (1622220201781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 16553267316 + ... + 16553267413.

It is an arithmetic number, because the mean of its divisors is an integer number (314512079935).

Almost surely, 2^{1622220201721} is an apocalyptic number.

It is an amenable number.

1622220201721 is a deficient number, since it is larger than the sum of its proper divisors (264852277889).

1622220201721 is an equidigital number, since it uses as much as digits as its factorization.

1622220201721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33106534743 (or 33106534736 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 28.

Adding to 1622220201721 its reverse (1271020222261), we get a palindrome (2893240423982).

The spelling of 1622220201721 in words is "one trillion, six hundred twenty-two billion, two hundred twenty million, two hundred one thousand, seven hundred twenty-one".