221117287 has 8 divisors (see below), whose sum is σ = 225689600. Its totient is φ = 216589464.

The previous prime is 221117279. The next prime is 221117329. The reversal of 221117287 is 782711122.

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 221117287 - 2³ = 221117279 is a prime.

It is a super-2 number, since 2×221117287² = 97785709220480738, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221117227) 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 7 ways as a sum of consecutive naturals, for example, 987 + ... + 21052.

It is an arithmetic number, because the mean of its divisors is an integer number (28211200).

Almost surely, 2^221117287 is an apocalyptic number.

221117287 is a deficient number, since it is larger than the sum of its proper divisors (4572313).

221117287 is a wasteful number, since it uses less digits than its factorization.

221117287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22245.

The product of its digits is 3136, while the sum is 31.

The square root of 221117287 is about 14870.0130127717. The cubic root of 221117287 is about 604.7012955257.

The spelling of 221117287 in words is "two hundred twenty-one million, one hundred seventeen thousand, two hundred eighty-seven".