221424623 has 16 divisors (see below), whose sum is σ = 258038784. Its totient is φ = 186093600.

The previous prime is 221424607. The next prime is 221424649. The reversal of 221424623 is 326424122.

It is a happy number.

It is not a de Polignac number, because 221424623 - 2⁴ = 221424607 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221424592 and 221424601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221424683) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74186 + ... + 77112.

It is an arithmetic number, because the mean of its divisors is an integer number (16127424).

Almost surely, 2^221424623 is an apocalyptic number.

221424623 is a deficient number, since it is larger than the sum of its proper divisors (36614161).

221424623 is a wasteful number, since it uses less digits than its factorization.

221424623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3142.

The product of its digits is 4608, while the sum is 26.

The square root of 221424623 is about 14880.3435108199. The cubic root of 221424623 is about 604.9813285680.

Adding to 221424623 its reverse (326424122), we get a palindrome (547848745).

The spelling of 221424623 in words is "two hundred twenty-one million, four hundred twenty-four thousand, six hundred twenty-three".