221663893237 has 2 divisors, whose sum is σ = 221663893238. Its totient is φ = 221663893236.

The previous prime is 221663893229. The next prime is 221663893291. The reversal of 221663893237 is 732398366122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 221214071556 + 449821681 = 470334^2 + 21209^2 .

It is a cyclic number.

It is not a de Polignac number, because 221663893237 - 2³ = 221663893229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221663893837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110831946618 + 110831946619.

It is an arithmetic number, because the mean of its divisors is an integer number (110831946619).

Almost surely, 2^221663893237 is an apocalyptic number.

It is an amenable number.

221663893237 is a deficient number, since it is larger than the sum of its proper divisors (1).

221663893237 is an equidigital number, since it uses as much as digits as its factorization.

221663893237 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3919104, while the sum is 52.

The spelling of 221663893237 in words is "two hundred twenty-one billion, six hundred sixty-three million, eight hundred ninety-three thousand, two hundred thirty-seven".