221423453 has 8 divisors (see below), whose sum is σ = 238872888. Its totient is φ = 204465664.

The previous prime is 221423431. The next prime is 221423459. The reversal of 221423453 is 354324122.

It can be written as a sum of positive squares in 4 ways, for example, as 144913444 + 76510009 = 12038^2 + 8747^2 .

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

It is not a de Polignac number, because 221423453 - 2⁸ = 221423197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221423459) 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, 121976 + ... + 123777.

It is an arithmetic number, because the mean of its divisors is an integer number (29859111).

Almost surely, 2^221423453 is an apocalyptic number.

It is an amenable number.

221423453 is a deficient number, since it is larger than the sum of its proper divisors (17449435).

221423453 is a wasteful number, since it uses less digits than its factorization.

221423453 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245823.

The product of its digits is 5760, while the sum is 26.

The square root of 221423453 is about 14880.3041971594. The cubic root of 221423453 is about 604.9802629993.

Adding to 221423453 its reverse (354324122), we get a palindrome (575747575).

The spelling of 221423453 in words is "two hundred twenty-one million, four hundred twenty-three thousand, four hundred fifty-three".