21026525 has 24 divisors (see below), whose sum is σ = 28998144. Its totient is φ = 15019200.

The previous prime is 21026519. The next prime is 21026549. The reversal of 21026525 is 52562012.

It is not a de Polignac number, because 21026525 - 2²⁴ = 4249309 is a prime.

It is a super-2 number, since 2×21026525² = 884229507151250, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21026525.

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 23 ways as a sum of consecutive naturals, for example, 9032 + ... + 11118.

It is an arithmetic number, because the mean of its divisors is an integer number (1208256).

Almost surely, 2^21026525 is an apocalyptic number.

21026525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21026525 is a deficient number, since it is larger than the sum of its proper divisors (7971619).

21026525 is a wasteful number, since it uses less digits than its factorization.

21026525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2141 (or 2136 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 21026525 is about 4585.4688964162. The cubic root of 21026525 is about 276.0085282319.

Adding to 21026525 its reverse (52562012), we get a palindrome (73588537).

The spelling of 21026525 in words is "twenty-one million, twenty-six thousand, five hundred twenty-five".