221423445 has 24 divisors (see below), whose sum is σ = 385178976. Its totient is φ = 117668448.

The previous prime is 221423431. The next prime is 221423459. The reversal of 221423445 is 544324122.

221423445 is a `hidden beast` number, since 2 + 214 + 2 + 3 + 445 = 666.

It is an interprime number because it is at equal distance from previous prime (221423431) and next prime (221423459).

It is not a de Polignac number, because 221423445 - 2⁹ = 221422933 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4042 + ... + 21428.

It is an arithmetic number, because the mean of its divisors is an integer number (16049124).

Almost surely, 2^221423445 is an apocalyptic number.

It is an amenable number.

221423445 is a deficient number, since it is larger than the sum of its proper divisors (163755531).

221423445 is a wasteful number, since it uses less digits than its factorization.

221423445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17681 (or 17678 counting only the distinct ones).

The product of its digits is 7680, while the sum is 27.

The square root of 221423445 is about 14880.3039283477. The cubic root of 221423445 is about 604.9802557134.

Adding to 221423445 its reverse (544324122), we get a palindrome (765747567).

The spelling of 221423445 in words is "two hundred twenty-one million, four hundred twenty-three thousand, four hundred forty-five".