221089918 has 16 divisors (see below), whose sum is σ = 387826560. Its totient is φ = 92549016.

The previous prime is 221089877. The next prime is 221089919. The reversal of 221089918 is 819980122.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221089919) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 183028 + ... + 184231.

It is an arithmetic number, because the mean of its divisors is an integer number (24239160).

Almost surely, 2^221089918 is an apocalyptic number.

221089918 is a deficient number, since it is larger than the sum of its proper divisors (166736642).

221089918 is a wasteful number, since it uses less digits than its factorization.

221089918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 367311.

The product of its (nonzero) digits is 20736, while the sum is 40.

The square root of 221089918 is about 14869.0927093754. The cubic root of 221089918 is about 604.6763453393.

The spelling of 221089918 in words is "two hundred twenty-one million, eighty-nine thousand, nine hundred eighteen".