21022125 has 32 divisors (see below), whose sum is σ = 35592960. Its totient is φ = 11016000.

The previous prime is 21022117. The next prime is 21022163. The reversal of 21022125 is 52122012.

It is not a de Polignac number, because 21022125 - 2³ = 21022117 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a Curzon number.

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 31 ways as a sum of consecutive naturals, for example, 22416 + ... + 23334.

It is an arithmetic number, because the mean of its divisors is an integer number (1112280).

Almost surely, 2^21022125 is an apocalyptic number.

21022125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21022125 is a deficient number, since it is larger than the sum of its proper divisors (14570835).

21022125 is an equidigital number, since it uses as much as digits as its factorization.

21022125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 998 (or 988 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 21022125 is about 4584.9890948616. The cubic root of 21022125 is about 275.9892744204.

Adding to 21022125 its reverse (52122012), we get a palindrome (73144137).

It can be divided in two parts, 210221 and 25, that multiplied together give a palindrome (5255525).

The spelling of 21022125 in words is "twenty-one million, twenty-two thousand, one hundred twenty-five".