21641282 has 16 divisors (see below), whose sum is σ = 35323512. Its totient is φ = 9884160.

The previous prime is 21641281. The next prime is 21641303. The reversal of 21641282 is 28214612.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6345361 + 15295921 = 2519^2 + 3911^2 .

It is a super-3 number, since 3×21641282³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is not an unprimeable number, because it can be changed into a prime (21641281) 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, 1769 + ... + 6812.

Almost surely, 2^21641282 is an apocalyptic number.

21641282 is a deficient number, since it is larger than the sum of its proper divisors (13682230).

21641282 is a wasteful number, since it uses less digits than its factorization.

21641282 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8693.

The product of its digits is 1536, while the sum is 26.

The square root of 21641282 is about 4652.0191315170. The cubic root of 21641282 is about 278.6726375432.

Adding to 21641282 its reverse (28214612), we get a palindrome (49855894).

The spelling of 21641282 in words is "twenty-one million, six hundred forty-one thousand, two hundred eighty-two".