18632264221 has 2 divisors, whose sum is σ = 18632264222. Its totient is φ = 18632264220.

The previous prime is 18632264153. The next prime is 18632264263. The reversal of 18632264221 is 12246223681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17825988196 + 806276025 = 133514^2 + 28395^2 .

It is an emirp because it is prime and its reverse (12246223681) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18632264221 - 2⁷ = 18632264093 is a prime.

It is a super-2 number, since 2×18632264221² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18632214221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9316132110 + 9316132111.

It is an arithmetic number, because the mean of its divisors is an integer number (9316132111).

Almost surely, 2^18632264221 is an apocalyptic number.

It is an amenable number.

18632264221 is a deficient number, since it is larger than the sum of its proper divisors (1).

18632264221 is an equidigital number, since it uses as much as digits as its factorization.

18632264221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 55296, while the sum is 37.

The spelling of 18632264221 in words is "eighteen billion, six hundred thirty-two million, two hundred sixty-four thousand, two hundred twenty-one".