221117999 has 4 divisors (see below), whose sum is σ = 223397664. Its totient is φ = 218838336.

The previous prime is 221117983. The next prime is 221118013. The reversal of 221117999 is 999711122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 221117999 - 2⁴ = 221117983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221117959) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1139687 + ... + 1139880.

It is an arithmetic number, because the mean of its divisors is an integer number (55849416).

Almost surely, 2^221117999 is an apocalyptic number.

221117999 is a deficient number, since it is larger than the sum of its proper divisors (2279665).

221117999 is an equidigital number, since it uses as much as digits as its factorization.

221117999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2279664.

The product of its digits is 20412, while the sum is 41.

The square root of 221117999 is about 14870.0369535519. The cubic root of 221117999 is about 604.7019445732.

The spelling of 221117999 in words is "two hundred twenty-one million, one hundred seventeen thousand, nine hundred ninety-nine".