221406260513 has 4 divisors (see below), whose sum is σ = 221958396228. Its totient is φ = 220854124800.

The previous prime is 221406260479. The next prime is 221406260561. The reversal of 221406260513 is 315062604122.

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 145520886784 + 75885373729 = 381472^2 + 275473^2 .

It is a cyclic number.

It is not a de Polignac number, because 221406260513 - 2¹² = 221406256417 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 221406260513.

It is not an unprimeable number, because it can be changed into a prime (221406260213) 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, 276067256 + ... + 276068057.

It is an arithmetic number, because the mean of its divisors is an integer number (55489599057).

Almost surely, 2^221406260513 is an apocalyptic number.

It is an amenable number.

221406260513 is a deficient number, since it is larger than the sum of its proper divisors (552135715).

221406260513 is an equidigital number, since it uses as much as digits as its factorization.

221406260513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 552135714.

The product of its (nonzero) digits is 17280, while the sum is 32.

Adding to 221406260513 its reverse (315062604122), we get a palindrome (536468864635).

The spelling of 221406260513 in words is "two hundred twenty-one billion, four hundred six million, two hundred sixty thousand, five hundred thirteen".