21106255 has 8 divisors (see below), whose sum is σ = 25415712. Its totient is φ = 16826208.

The previous prime is 21106237. The next prime is 21106259. The reversal of 21106255 is 55260112.

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

It is a cyclic number.

It is not a de Polignac number, because 21106255 - 2²³ = 12717647 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 (21106259) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 5739 + ... + 8668.

It is an arithmetic number, because the mean of its divisors is an integer number (3176964).

Almost surely, 2^21106255 is an apocalyptic number.

21106255 is a deficient number, since it is larger than the sum of its proper divisors (4309457).

21106255 is a wasteful number, since it uses less digits than its factorization.

21106255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14705.

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 21106255 is about 4594.1544379788. The cubic root of 21106255 is about 276.3569516878.

Adding to 21106255 its reverse (55260112), we get a palindrome (76366367).

It can be divided in two parts, 21 and 106255, that added together give a square (106276 = 326²).

The spelling of 21106255 in words is "twenty-one million, one hundred six thousand, two hundred fifty-five".