21127125 has 32 divisors (see below), whose sum is σ = 35852544. Its totient is φ = 11044800.

The previous prime is 21127121. The next prime is 21127159. The reversal of 21127125 is 52172112.

It is not a de Polignac number, because 21127125 - 2² = 21127121 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21127121) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19344 + ... + 20406.

It is an arithmetic number, because the mean of its divisors is an integer number (1120392).

Almost surely, 2^21127125 is an apocalyptic number.

21127125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21127125 is a deficient number, since it is larger than the sum of its proper divisors (14725419).

21127125 is a wasteful number, since it uses less digits than its factorization.

21127125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1134 (or 1124 counting only the distinct ones).

The product of its digits is 280, while the sum is 21.

The square root of 21127125 is about 4596.4252414240. The cubic root of 21127125 is about 276.4480095223.

Adding to 21127125 its reverse (52172112), we get a palindrome (73299237).

The spelling of 21127125 in words is "twenty-one million, one hundred twenty-seven thousand, one hundred twenty-five".