221760091 has 8 divisors (see below), whose sum is σ = 253952000. Its totient is φ = 189696168.

The previous prime is 221760083. The next prime is 221760107. The reversal of 221760091 is 190067122.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221760091 - 2³ = 221760083 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221760061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28251 + ... + 35236.

It is an arithmetic number, because the mean of its divisors is an integer number (31744000).

Almost surely, 2^221760091 is an apocalyptic number.

221760091 is a deficient number, since it is larger than the sum of its proper divisors (32191909).

221760091 is an equidigital number, since it uses as much as digits as its factorization.

221760091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63993.

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 221760091 is about 14891.6114306008. The cubic root of 221760091 is about 605.2866988050.

The spelling of 221760091 in words is "two hundred twenty-one million, seven hundred sixty thousand, ninety-one".