221516249 has 2 divisors, whose sum is σ = 221516250. Its totient is φ = 221516248.

The previous prime is 221516227. The next prime is 221516287. The reversal of 221516249 is 942615122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 211906249 + 9610000 = 14557^2 + 3100^2 .

It is a cyclic number.

It is not a de Polignac number, because 221516249 - 2⁸ = 221515993 is a prime.

It is not a weakly prime, because it can be changed into another prime (221516209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110758124 + 110758125.

It is an arithmetic number, because the mean of its divisors is an integer number (110758125).

Almost surely, 2^221516249 is an apocalyptic number.

It is an amenable number.

221516249 is a deficient number, since it is larger than the sum of its proper divisors (1).

221516249 is an equidigital number, since it uses as much as digits as its factorization.

221516249 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8640, while the sum is 32.

The square root of 221516249 is about 14883.4219519572. The cubic root of 221516249 is about 605.0647645988.

The spelling of 221516249 in words is "two hundred twenty-one million, five hundred sixteen thousand, two hundred forty-nine".