21544125 has 32 divisors (see below), whose sum is σ = 36386688. Its totient is φ = 11318400.

The previous prime is 21544109. The next prime is 21544139. The reversal of 21544125 is 52144512.

It is not a de Polignac number, because 21544125 - 2⁴ = 21544109 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21544095 and 21544104.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 26982 + ... + 27768.

It is an arithmetic number, because the mean of its divisors is an integer number (1137084).

Almost surely, 2^21544125 is an apocalyptic number.

21544125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21544125 is a deficient number, since it is larger than the sum of its proper divisors (14842563).

21544125 is an equidigital number, since it uses as much as digits as its factorization.

21544125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 878 (or 868 counting only the distinct ones).

The product of its digits is 1600, while the sum is 24.

The square root of 21544125 is about 4641.5649300640. The cubic root of 21544125 is about 278.2549848998.

Adding to 21544125 its reverse (52144512), we get a palindrome (73688637).

The spelling of 21544125 in words is "twenty-one million, five hundred forty-four thousand, one hundred twenty-five".