221864319 has 8 divisors (see below), whose sum is σ = 328687920. Its totient is φ = 147909528.

The previous prime is 221864267. The next prime is 221864323. The reversal of 221864319 is 913468122.

221864319 is a `hidden beast` number, since 2 + 2 + 1 + 8 + 643 + 1 + 9 = 666.

It is not a de Polignac number, because 221864319 - 2¹³ = 221856127 is a prime.

It is a super-2 number, since 2×221864319² = 98447552090667522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221864329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4108572 + ... + 4108625.

It is an arithmetic number, because the mean of its divisors is an integer number (41085990).

Almost surely, 2^221864319 is an apocalyptic number.

221864319 is a deficient number, since it is larger than the sum of its proper divisors (106823601).

221864319 is an equidigital number, since it uses as much as digits as its factorization.

221864319 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8217206 (or 8217200 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 221864319 is about 14895.1105736077. The cubic root of 221864319 is about 605.3815128907.

The spelling of 221864319 in words is "two hundred twenty-one million, eight hundred sixty-four thousand, three hundred nineteen".