21532045 has 16 divisors (see below), whose sum is σ = 26525232. Its totient is φ = 16773120.

The previous prime is 21532033. The next prime is 21532051. The reversal of 21532045 is 54023512.

It can be written as a sum of positive squares in 8 ways, for example, as 4076361 + 17455684 = 2019^2 + 4178^2 .

It is not a de Polignac number, because 21532045 - 2¹¹ = 21529997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 50935 + ... + 51355.

It is an arithmetic number, because the mean of its divisors is an integer number (1657827).

Almost surely, 2^21532045 is an apocalyptic number.

It is an amenable number.

21532045 is a deficient number, since it is larger than the sum of its proper divisors (4993187).

21532045 is a wasteful number, since it uses less digits than its factorization.

21532045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 672.

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 21532045 is about 4640.2634623478. The cubic root of 21532045 is about 278.2029684196.

Adding to 21532045 its reverse (54023512), we get a palindrome (75555557).

The spelling of 21532045 in words is "twenty-one million, five hundred thirty-two thousand, forty-five".