21523282 has 16 divisors (see below), whose sum is σ = 35354592. Its totient is φ = 9745920.

The previous prime is 21523277. The next prime is 21523283. The reversal of 21523282 is 28232512.

It is not an unprimeable number, because it can be changed into a prime (21523283) 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, 4498 + ... + 7954.

It is an arithmetic number, because the mean of its divisors is an integer number (2209662).

Almost surely, 2^21523282 is an apocalyptic number.

21523282 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21523282 is a deficient number, since it is larger than the sum of its proper divisors (13831310).

21523282 is a wasteful number, since it uses less digits than its factorization.

21523282 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3753.

The product of its digits is 1920, while the sum is 25.

The square root of 21523282 is about 4639.3191310795. The cubic root of 21523282 is about 278.1652227649.

Adding to 21523282 its reverse (28232512), we get a palindrome (49755794).

The spelling of 21523282 in words is "twenty-one million, five hundred twenty-three thousand, two hundred eighty-two".