21268575 has 48 divisors (see below), whose sum is σ = 39655200. Its totient is φ = 11314080.

The previous prime is 21268567. The next prime is 21268579. The reversal of 21268575 is 57586212.

It is a happy number.

21268575 is a `hidden beast` number, since 21 + 2 + 68 + 575 = 666.

It is not a de Polignac number, because 21268575 - 2³ = 21268567 is a prime.

Its product of digits (33600) is a multiple of the sum of its prime factors (420).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21268579) 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 47 ways as a sum of consecutive naturals, for example, 54481 + ... + 54869.

It is an arithmetic number, because the mean of its divisors is an integer number (826150).

Almost surely, 2^21268575 is an apocalyptic number.

21268575 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21268575 is a deficient number, since it is larger than the sum of its proper divisors (18386625).

21268575 is an frugal number, since it uses more digits than its factorization.

21268575 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 420 (or 397 counting only the distinct ones).

The product of its digits is 33600, while the sum is 36.

The square root of 21268575 is about 4611.7865301855. The cubic root of 21268575 is about 277.0635945512.

It can be divided in two parts, 2126 and 8575, that added together give a palindrome (10701).

The spelling of 21268575 in words is "twenty-one million, two hundred sixty-eight thousand, five hundred seventy-five".