221118081 has 4 divisors (see below), whose sum is σ = 294824112. Its totient is φ = 147412052.

The previous prime is 221118013. The next prime is 221118089. The reversal of 221118081 is 180811122.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 221118081 - 2¹⁷ = 220987009 is a prime.

It is a super-2 number, since 2×221118081² = 97786411490245122, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (221118089) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36853011 + ... + 36853016.

It is an arithmetic number, because the mean of its divisors is an integer number (73706028).

Almost surely, 2^221118081 is an apocalyptic number.

It is an amenable number.

221118081 is a deficient number, since it is larger than the sum of its proper divisors (73706031).

221118081 is an equidigital number, since it uses as much as digits as its factorization.

221118081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73706030.

The product of its (nonzero) digits is 256, while the sum is 24.

The square root of 221118081 is about 14870.0397107741. The cubic root of 221118081 is about 604.7020193230.

The spelling of 221118081 in words is "two hundred twenty-one million, one hundred eighteen thousand, eighty-one".