221013644 has 6 divisors (see below), whose sum is σ = 386773884. Its totient is φ = 110506820.

The previous prime is 221013641. The next prime is 221013659. The reversal of 221013644 is 446310122.

It is not an unprimeable number, because it can be changed into a prime (221013641) 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, 27626702 + ... + 27626709.

It is an arithmetic number, because the mean of its divisors is an integer number (64462314).

Almost surely, 2^221013644 is an apocalyptic number.

It is an amenable number.

221013644 is a deficient number, since it is larger than the sum of its proper divisors (165760240).

221013644 is a wasteful number, since it uses less digits than its factorization.

221013644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55253415 (or 55253413 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 221013644 is about 14866.5276376160. The cubic root of 221013644 is about 604.6068014047.

Adding to 221013644 its reverse (446310122), we get a palindrome (667323766).

The spelling of 221013644 in words is "two hundred twenty-one million, thirteen thousand, six hundred forty-four".