221645266385 has 8 divisors (see below), whose sum is σ = 273162815016. Its totient is φ = 172523882880.

The previous prime is 221645266379. The next prime is 221645266417. The reversal of 221645266385 is 583662546122.

It can be written as a sum of positive squares in 4 ways, for example, as 83294000449 + 138351265936 = 288607^2 + 371956^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 221645266385 - 2²⁴ = 221628489169 is a prime.

It is a super-2 number, since 2×221645266385² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 599041076 + ... + 599041445.

It is an arithmetic number, because the mean of its divisors is an integer number (34145351877).

Almost surely, 2^221645266385 is an apocalyptic number.

It is an amenable number.

221645266385 is a deficient number, since it is larger than the sum of its proper divisors (51517548631).

221645266385 is a wasteful number, since it uses less digits than its factorization.

221645266385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1198082563.

The product of its digits is 4147200, while the sum is 50.

The spelling of 221645266385 in words is "two hundred twenty-one billion, six hundred forty-five million, two hundred sixty-six thousand, three hundred eighty-five".