21328527 has 16 divisors (see below), whose sum is σ = 32025600. Its totient is φ = 12508800.

The previous prime is 21328501. The next prime is 21328537. The reversal of 21328527 is 72582312.

It is not a de Polignac number, because 21328527 - 2⁷ = 21328399 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21328494 and 21328503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21328537) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9402 + ... + 11447.

It is an arithmetic number, because the mean of its divisors is an integer number (2001600).

Almost surely, 2^21328527 is an apocalyptic number.

21328527 is a deficient number, since it is larger than the sum of its proper divisors (10697073).

21328527 is a wasteful number, since it uses less digits than its factorization.

21328527 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20894.

The product of its digits is 6720, while the sum is 30.

The square root of 21328527 is about 4618.2818233625. The cubic root of 21328527 is about 277.3236798921.

It can be divided in two parts, 213285 and 27, that added together give a palindrome (213312).

The spelling of 21328527 in words is "twenty-one million, three hundred twenty-eight thousand, five hundred twenty-seven".