221668833 has 4 divisors (see below), whose sum is σ = 295558448. Its totient is φ = 147779220.

The previous prime is 221668819. The next prime is 221668859. The reversal of 221668833 is 338866122.

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 de Polignac number, because none of the positive numbers 2^k-221668833 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221668791 and 221668800.

It is not an unprimeable number, because it can be changed into a prime (221668883) 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, 36944803 + ... + 36944808.

It is an arithmetic number, because the mean of its divisors is an integer number (73889612).

Almost surely, 2^221668833 is an apocalyptic number.

It is an amenable number.

221668833 is a deficient number, since it is larger than the sum of its proper divisors (73889615).

221668833 is an equidigital number, since it uses as much as digits as its factorization.

221668833 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73889614.

The product of its digits is 82944, while the sum is 39.

The square root of 221668833 is about 14888.5470412663. The cubic root of 221668833 is about 605.2036588675.

The spelling of 221668833 in words is "two hundred twenty-one million, six hundred sixty-eight thousand, eight hundred thirty-three".