221325233661 has 24 divisors (see below), whose sum is σ = 377960993280. Its totient is φ = 122110472736.

The previous prime is 221325233653. The next prime is 221325233683. The reversal of 221325233661 is 166332523122.

221325233661 is a `hidden beast` number, since 2 + 2 + 13 + 252 + 336 + 61 = 666.

It is not a de Polignac number, because 221325233661 - 2³ = 221325233653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221325233621) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 60568845 + ... + 60572498.

It is an arithmetic number, because the mean of its divisors is an integer number (15748374720).

Almost surely, 2^221325233661 is an apocalyptic number.

221325233661 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

221325233661 is a deficient number, since it is larger than the sum of its proper divisors (156635759619).

221325233661 is a wasteful number, since it uses less digits than its factorization.

221325233661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121141385 (or 121141382 counting only the distinct ones).

The product of its digits is 77760, while the sum is 36.

Adding to 221325233661 its reverse (166332523122), we get a palindrome (387657756783).

The spelling of 221325233661 in words is "two hundred twenty-one billion, three hundred twenty-five million, two hundred thirty-three thousand, six hundred sixty-one".