221349897 has 12 divisors (see below), whose sum is σ = 322662340. Its totient is φ = 146212128.

The previous prime is 221349881. The next prime is 221349899. The reversal of 221349897 is 798943122.

221349897 is a `hidden beast` number, since 221 + 349 + 89 + 7 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 194351481 + 26998416 = 13941^2 + 5196^2 .

It is not a de Polignac number, because 221349897 - 2⁴ = 221349881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221349899) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 111838 + ... + 113799.

Almost surely, 2^221349897 is an apocalyptic number.

It is an amenable number.

221349897 is a deficient number, since it is larger than the sum of its proper divisors (101312443).

221349897 is a wasteful number, since it uses less digits than its factorization.

221349897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225752 (or 225749 counting only the distinct ones).

The product of its digits is 217728, while the sum is 45.

The square root of 221349897 is about 14877.8324026049. The cubic root of 221349897 is about 604.9132648921.

The spelling of 221349897 in words is "two hundred twenty-one million, three hundred forty-nine thousand, eight hundred ninety-seven".