221647479 has 8 divisors (see below), whose sum is σ = 312914160. Its totient is φ = 139072896.

The previous prime is 221647477. The next prime is 221647487. The reversal of 221647479 is 974746122.

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

It is not a de Polignac number, because 221647479 - 2¹ = 221647477 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221647479.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221647471) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2172964 + ... + 2173065.

It is an arithmetic number, because the mean of its divisors is an integer number (39114270).

Almost surely, 2^221647479 is an apocalyptic number.

221647479 is a deficient number, since it is larger than the sum of its proper divisors (91266681).

221647479 is a wasteful number, since it uses less digits than its factorization.

221647479 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4346049.

The product of its digits is 169344, while the sum is 42.

The square root of 221647479 is about 14887.8298955892. The cubic root of 221647479 is about 605.1842245703.

The spelling of 221647479 in words is "two hundred twenty-one million, six hundred forty-seven thousand, four hundred seventy-nine".