221794915 has 8 divisors (see below), whose sum is σ = 267787728. Its totient is φ = 176346720.

The previous prime is 221794891. The next prime is 221794919. The reversal of 221794915 is 519497122.

It is a happy number.

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

It is not a de Polignac number, because 221794915 - 2⁵ = 221794883 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221794919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 135256 + ... + 136885.

It is an arithmetic number, because the mean of its divisors is an integer number (33473466).

Almost surely, 2^221794915 is an apocalyptic number.

221794915 is a deficient number, since it is larger than the sum of its proper divisors (45992813).

221794915 is a wasteful number, since it uses less digits than its factorization.

221794915 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272309.

The product of its digits is 45360, while the sum is 40.

The square root of 221794915 is about 14892.7806335822. The cubic root of 221794915 is about 605.3183807917.

The spelling of 221794915 in words is "two hundred twenty-one million, seven hundred ninety-four thousand, nine hundred fifteen".