21232255 has 8 divisors (see below), whose sum is σ = 27795024. Its totient is φ = 15441600.

The previous prime is 21232249. The next prime is 21232259. The reversal of 21232255 is 55223212.

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

It is not a de Polignac number, because 21232255 - 2³ = 21232247 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 (21232259) 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 7 ways as a sum of consecutive naturals, for example, 192966 + ... + 193075.

It is an arithmetic number, because the mean of its divisors is an integer number (3474378).

Almost surely, 2^21232255 is an apocalyptic number.

21232255 is a deficient number, since it is larger than the sum of its proper divisors (6562769).

21232255 is a wasteful number, since it uses less digits than its factorization.

21232255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386057.

The product of its digits is 1200, while the sum is 22.

The square root of 21232255 is about 4607.8471111789. The cubic root of 21232255 is about 276.9057923586.

Adding to 21232255 its reverse (55223212), we get a palindrome (76455467).

The spelling of 21232255 in words is "twenty-one million, two hundred thirty-two thousand, two hundred fifty-five".