22135201621 has 4 divisors (see below), whose sum is σ = 23837909452. Its totient is φ = 20432493792.

The previous prime is 22135201619. The next prime is 22135201663. The reversal of 22135201621 is 12610253122.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12610253122 = 2 ⋅6305126561.

It can be written as a sum of positive squares in 2 ways, for example, as 2307745521 + 19827456100 = 48039^2 + 140810^2 .

It is a cyclic number.

It is not a de Polignac number, because 22135201621 - 2¹ = 22135201619 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22135201321) 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, 851353896 + ... + 851353921.

It is an arithmetic number, because the mean of its divisors is an integer number (5959477363).

Almost surely, 2^22135201621 is an apocalyptic number.

It is an amenable number.

22135201621 is a deficient number, since it is larger than the sum of its proper divisors (1702707831).

22135201621 is a wasteful number, since it uses less digits than its factorization.

22135201621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1702707830.

The product of its (nonzero) digits is 1440, while the sum is 25.

Adding to 22135201621 its reverse (12610253122), we get a palindrome (34745454743).

The spelling of 22135201621 in words is "twenty-two billion, one hundred thirty-five million, two hundred one thousand, six hundred twenty-one".