221566039 has 2 divisors, whose sum is σ = 221566040. Its totient is φ = 221566038.

The previous prime is 221566031. The next prime is 221566067. The reversal of 221566039 is 930665122.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 221566039 - 2³ = 221566031 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221565995 and 221566013.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221566031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110783019 + 110783020.

It is an arithmetic number, because the mean of its divisors is an integer number (110783020).

Almost surely, 2^221566039 is an apocalyptic number.

221566039 is a deficient number, since it is larger than the sum of its proper divisors (1).

221566039 is an equidigital number, since it uses as much as digits as its factorization.

221566039 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 221566039 is about 14885.0945243892. The cubic root of 221566039 is about 605.1100944830.

The spelling of 221566039 in words is "two hundred twenty-one million, five hundred sixty-six thousand, thirty-nine".