21534525 has 48 divisors (see below), whose sum is σ = 40285120. Its totient is φ = 11275200.

The previous prime is 21534517. The next prime is 21534533. The reversal of 21534525 is 52543512.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21534517) and next prime (21534533).

It is not a de Polignac number, because 21534525 - 2³ = 21534517 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 40914 + ... + 41436.

Almost surely, 2^21534525 is an apocalyptic number.

21534525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21534525 is a deficient number, since it is larger than the sum of its proper divisors (18750595).

21534525 is a wasteful number, since it uses less digits than its factorization.

21534525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 603 (or 592 counting only the distinct ones).

The product of its digits is 6000, while the sum is 27.

The square root of 21534525 is about 4640.5306808597. The cubic root of 21534525 is about 278.2136488864.

The spelling of 21534525 in words is "twenty-one million, five hundred thirty-four thousand, five hundred twenty-five".