221019423 has 4 divisors (see below), whose sum is σ = 294692568. Its totient is φ = 147346280.

The previous prime is 221019377. The next prime is 221019433. The reversal of 221019423 is 324910122.

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 221019423 - 2⁹ = 221018911 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221019393 and 221019402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221019433) 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 3 ways as a sum of consecutive naturals, for example, 36836568 + ... + 36836573.

It is an arithmetic number, because the mean of its divisors is an integer number (73673142).

Almost surely, 2^221019423 is an apocalyptic number.

221019423 is a deficient number, since it is larger than the sum of its proper divisors (73673145).

221019423 is an equidigital number, since it uses as much as digits as its factorization.

221019423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73673144.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 221019423 is about 14866.7219991496. The cubic root of 221019423 is about 604.6120710526.

Adding to 221019423 its reverse (324910122), we get a palindrome (545929545).

The spelling of 221019423 in words is "two hundred twenty-one million, nineteen thousand, four hundred twenty-three".