221040993 has 4 divisors (see below), whose sum is σ = 294721328. Its totient is φ = 147360660.

The previous prime is 221040979. The next prime is 221041019. The reversal of 221040993 is 399040122.

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 not a de Polignac number, because 221040993 - 2⁴ = 221040977 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 221040993.

It is not an unprimeable number, because it can be changed into a prime (221040893) 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 3 ways as a sum of consecutive naturals, for example, 36840163 + ... + 36840168.

It is an arithmetic number, because the mean of its divisors is an integer number (73680332).

Almost surely, 2^221040993 is an apocalyptic number.

It is an amenable number.

221040993 is a deficient number, since it is larger than the sum of its proper divisors (73680335).

221040993 is an equidigital number, since it uses as much as digits as its factorization.

221040993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73680334.

The product of its (nonzero) digits is 3888, while the sum is 30.

The square root of 221040993 is about 14867.4474271813. The cubic root of 221040993 is about 604.6317390950.

The spelling of 221040993 in words is "two hundred twenty-one million, forty thousand, nine hundred ninety-three".