21112525 has 24 divisors (see below), whose sum is σ = 30109184. Its totient is φ = 14385600.

The previous prime is 21112433. The next prime is 21112547. The reversal of 21112525 is 52521112.

It is not a de Polignac number, because 21112525 - 2¹³ = 21104333 is a prime.

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 23 ways as a sum of consecutive naturals, for example, 38755 + ... + 39295.

Almost surely, 2^21112525 is an apocalyptic number.

21112525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21112525 is a deficient number, since it is larger than the sum of its proper divisors (8996659).

21112525 is a wasteful number, since it uses less digits than its factorization.

21112525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 781 (or 776 counting only the distinct ones).

The product of its digits is 200, while the sum is 19.

The square root of 21112525 is about 4594.8367762087. The cubic root of 21112525 is about 276.3843146114.

Adding to 21112525 its reverse (52521112), we get a palindrome (73633637).

The spelling of 21112525 in words is "twenty-one million, one hundred twelve thousand, five hundred twenty-five".