221745894449 has 2 divisors, whose sum is σ = 221745894450. Its totient is φ = 221745894448.

The previous prime is 221745894313. The next prime is 221745894463. The reversal of 221745894449 is 944498547122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 173722240000 + 48023654449 = 416800^2 + 219143^2 .

It is a cyclic number.

It is not a de Polignac number, because 221745894449 - 2²⁰ = 221744845873 is a prime.

It is not a weakly prime, because it can be changed into another prime (221745894479) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110872947224 + 110872947225.

It is an arithmetic number, because the mean of its divisors is an integer number (110872947225).

Almost surely, 2^221745894449 is an apocalyptic number.

It is an amenable number.

221745894449 is a deficient number, since it is larger than the sum of its proper divisors (1).

221745894449 is an equidigital number, since it uses as much as digits as its factorization.

221745894449 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23224320, while the sum is 59.

The spelling of 221745894449 in words is "two hundred twenty-one billion, seven hundred forty-five million, eight hundred ninety-four thousand, four hundred forty-nine".