21459425 has 12 divisors (see below), whose sum is σ = 28657020. Its totient is φ = 15846720.

The previous prime is 21459419. The next prime is 21459443. The reversal of 21459425 is 52495412.

It can be written as a sum of positive squares in 6 ways, for example, as 8549776 + 12909649 = 2924^2 + 3593^2 .

It is not a de Polignac number, because 21459425 - 2⁸ = 21459169 is a prime.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21459391 and 21459400.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 32690 + ... + 33339.

It is an arithmetic number, because the mean of its divisors is an integer number (2388085).

Almost surely, 2^21459425 is an apocalyptic number.

21459425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21459425 is a deficient number, since it is larger than the sum of its proper divisors (7197595).

21459425 is a wasteful number, since it uses less digits than its factorization.

21459425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66052 (or 66047 counting only the distinct ones).

The product of its digits is 14400, while the sum is 32.

The square root of 21459425 is about 4632.4318667413. The cubic root of 21459425 is about 277.8898559576.

The spelling of 21459425 in words is "twenty-one million, four hundred fifty-nine thousand, four hundred twenty-five".