221891873 has 8 divisors (see below), whose sum is σ = 257376192. Its totient is φ = 187353936.

The previous prime is 221891851. The next prime is 221891897. The reversal of 221891873 is 378198122.

221891873 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 221891873 - 2⁶ = 221891809 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221891873.

It is not an unprimeable number, because it can be changed into a prime (221891573) 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, 236090 + ... + 237027.

It is an arithmetic number, because the mean of its divisors is an integer number (32172024).

Almost surely, 2^221891873 is an apocalyptic number.

It is an amenable number.

221891873 is a deficient number, since it is larger than the sum of its proper divisors (35484319).

221891873 is an equidigital number, since it uses as much as digits as its factorization.

221891873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 473191.

The product of its digits is 48384, while the sum is 41.

The square root of 221891873 is about 14896.0354792811. The cubic root of 221891873 is about 605.4065732396.

The spelling of 221891873 in words is "two hundred twenty-one million, eight hundred ninety-one thousand, eight hundred seventy-three".