221650109 has 2 divisors, whose sum is σ = 221650110. Its totient is φ = 221650108.

The previous prime is 221650061. The next prime is 221650111. The reversal of 221650109 is 901056122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 195384484 + 26265625 = 13978^2 + 5125^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221650109 is a prime.

Together with 221650111, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221650159) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110825054 + 110825055.

It is an arithmetic number, because the mean of its divisors is an integer number (110825055).

Almost surely, 2^221650109 is an apocalyptic number.

It is an amenable number.

221650109 is a deficient number, since it is larger than the sum of its proper divisors (1).

221650109 is an equidigital number, since it uses as much as digits as its factorization.

221650109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 26.

The square root of 221650109 is about 14887.9182225051. The cubic root of 221650109 is about 605.1866182034.

It can be divided in two parts, 2216 and 50109, that added together give a palindrome (52325).

The spelling of 221650109 in words is "two hundred twenty-one million, six hundred fifty thousand, one hundred nine".