221495849 has 2 divisors, whose sum is σ = 221495850. Its totient is φ = 221495848.

The previous prime is 221495809. The next prime is 221495867. The reversal of 221495849 is 948594122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 208282624 + 13213225 = 14432^2 + 3635^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221495849 is a prime.

It is a super-2 number, since 2×221495849² = 98120822248461602, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (221495809) 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, 110747924 + 110747925.

It is an arithmetic number, because the mean of its divisors is an integer number (110747925).

Almost surely, 2^221495849 is an apocalyptic number.

It is an amenable number.

221495849 is a deficient number, since it is larger than the sum of its proper divisors (1).

221495849 is an equidigital number, since it uses as much as digits as its factorization.

221495849 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 207360, while the sum is 44.

The square root of 221495849 is about 14882.7366099115. The cubic root of 221495849 is about 605.0461900394.

The spelling of 221495849 in words is "two hundred twenty-one million, four hundred ninety-five thousand, eight hundred forty-nine".