21017325 has 96 divisors (see below), whose sum is σ = 43648000. Its totient is φ = 8890560.

The previous prime is 21017317. The next prime is 21017327. The reversal of 21017325 is 52371012.

It is not a de Polignac number, because 21017325 - 2³ = 21017317 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21017327) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 488754 + ... + 488796.

Almost surely, 2^21017325 is an apocalyptic number.

21017325 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21017325 is an abundant number, since it is smaller than the sum of its proper divisors (22630675).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21017325 is a wasteful number, since it uses less digits than its factorization.

21017325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 21017325 is about 4584.4656177138. The cubic root of 21017325 is about 275.9682671982.

Adding to 21017325 its reverse (52371012), we get a palindrome (73388337).

The spelling of 21017325 in words is "twenty-one million, seventeen thousand, three hundred twenty-five".