21422125 has 24 divisors (see below), whose sum is σ = 28447848. Its totient is φ = 16102400.

The previous prime is 21422119. The next prime is 21422129. The reversal of 21422125 is 52122412.

It can be written as a sum of positive squares in 12 ways, for example, as 7739524 + 13682601 = 2782^2 + 3699^2 .

It is not a de Polignac number, because 21422125 - 2³ = 21422117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21422129) by changing a digit.

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, 35829 + ... + 36421.

It is an arithmetic number, because the mean of its divisors is an integer number (1185327).

Almost surely, 2^21422125 is an apocalyptic number.

21422125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21422125 is a deficient number, since it is larger than the sum of its proper divisors (7025723).

21422125 is an equidigital number, since it uses as much as digits as its factorization.

21422125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642 (or 615 counting only the distinct ones).

The product of its digits is 320, while the sum is 19.

The square root of 21422125 is about 4628.4041526211. The cubic root of 21422125 is about 277.7287565346.

Adding to 21422125 its reverse (52122412), we get a palindrome (73544537).

The spelling of 21422125 in words is "twenty-one million, four hundred twenty-two thousand, one hundred twenty-five".