21346725 has 12 divisors (see below), whose sum is σ = 35293376. Its totient is φ = 11384880.

The previous prime is 21346711. The next prime is 21346751. The reversal of 21346725 is 52764312.

It is not a de Polignac number, because 21346725 - 2⁸ = 21346469 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21346692 and 21346701.

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, 142237 + ... + 142386.

Almost surely, 2^21346725 is an apocalyptic number.

21346725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21346725 is a deficient number, since it is larger than the sum of its proper divisors (13946651).

21346725 is a wasteful number, since it uses less digits than its factorization.

21346725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284636 (or 284631 counting only the distinct ones).

The product of its digits is 10080, while the sum is 30.

The square root of 21346725 is about 4620.2516165248. The cubic root of 21346725 is about 277.4025304956.

The spelling of 21346725 in words is "twenty-one million, three hundred forty-six thousand, seven hundred twenty-five".