221479399 has 2 divisors, whose sum is σ = 221479400. Its totient is φ = 221479398.

The previous prime is 221479393. The next prime is 221479439. The reversal of 221479399 is 993974122.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221479399 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221479393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110739699 + 110739700.

It is an arithmetic number, because the mean of its divisors is an integer number (110739700).

Almost surely, 2^221479399 is an apocalyptic number.

221479399 is a deficient number, since it is larger than the sum of its proper divisors (1).

221479399 is an equidigital number, since it uses as much as digits as its factorization.

221479399 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 244944, while the sum is 46.

The square root of 221479399 is about 14882.1839459133. The cubic root of 221479399 is about 605.0312111941.

The spelling of 221479399 in words is "two hundred twenty-one million, four hundred seventy-nine thousand, three hundred ninety-nine".