221423221405 has 4 divisors (see below), whose sum is σ = 265707865692. Its totient is φ = 177138577120.

The previous prime is 221423221379. The next prime is 221423221417. The reversal of 221423221405 is 504122324122.

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 61332008409 + 160091212996 = 247653^2 + 400114^2 .

It is not a de Polignac number, because 221423221405 - 2²⁵ = 221389666973 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22142322136 + ... + 22142322145.

It is an arithmetic number, because the mean of its divisors is an integer number (66426966423).

Almost surely, 2^221423221405 is an apocalyptic number.

It is an amenable number.

221423221405 is a deficient number, since it is larger than the sum of its proper divisors (44284644287).

221423221405 is an equidigital number, since it uses as much as digits as its factorization.

221423221405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44284644286.

The product of its (nonzero) digits is 7680, while the sum is 28.

Adding to 221423221405 its reverse (504122324122), we get a palindrome (725545545527).

The spelling of 221423221405 in words is "two hundred twenty-one billion, four hundred twenty-three million, two hundred twenty-one thousand, four hundred five".