21383255 has 16 divisors (see below), whose sum is σ = 26425344. Its totient is φ = 16601760.

The previous prime is 21383249. The next prime is 21383267. The reversal of 21383255 is 55238312.

It is not a de Polignac number, because 21383255 - 2⁴ = 21383239 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 58082 + ... + 58448.

It is an arithmetic number, because the mean of its divisors is an integer number (1651584).

Almost surely, 2^21383255 is an apocalyptic number.

21383255 is a deficient number, since it is larger than the sum of its proper divisors (5042089).

21383255 is a wasteful number, since it uses less digits than its factorization.

21383255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 686.

The product of its digits is 7200, while the sum is 29.

The square root of 21383255 is about 4624.2031746021. The cubic root of 21383255 is about 277.5606771517.

The spelling of 21383255 in words is "twenty-one million, three hundred eighty-three thousand, two hundred fifty-five".