21363525 has 18 divisors (see below), whose sum is σ = 38264850. Its totient is φ = 11393760.

The previous prime is 21363497. The next prime is 21363593. The reversal of 21363525 is 52536312.

21363525 = 629² + 630² + ... + 678².

21363525 is a `hidden beast` number, since 2 + 1 + 3 + 635 + 25 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 74529 + 21288996 = 273^2 + 4614^2 .

It is not a de Polignac number, because 21363525 - 2¹¹ = 21361477 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 47250 + ... + 47699.

It is an arithmetic number, because the mean of its divisors is an integer number (2125825).

Almost surely, 2^21363525 is an apocalyptic number.

21363525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21363525 is a deficient number, since it is larger than the sum of its proper divisors (16901325).

21363525 is a wasteful number, since it uses less digits than its factorization.

21363525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94965 (or 94957 counting only the distinct ones).

The product of its digits is 5400, while the sum is 27.

The square root of 21363525 is about 4622.0693417559. The cubic root of 21363525 is about 277.4752838956.

Adding to 21363525 its reverse (52536312), we get a palindrome (73899837).

The spelling of 21363525 in words is "twenty-one million, three hundred sixty-three thousand, five hundred twenty-five".