821317925 has 24 divisors (see below), whose sum is σ = 1064515200. Its totient is φ = 627422400.

The previous prime is 821317909. The next prime is 821317927. The reversal of 821317925 is 529713128.

It is not a de Polignac number, because 821317925 - 2⁴ = 821317909 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821317927) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 586376 + ... + 587774.

It is an arithmetic number, because the mean of its divisors is an integer number (44354800).

Almost surely, 2^821317925 is an apocalyptic number.

It is an amenable number.

821317925 is a deficient number, since it is larger than the sum of its proper divisors (243197275).

821317925 is a wasteful number, since it uses less digits than its factorization.

821317925 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2453 (or 2448 counting only the distinct ones).

The product of its digits is 30240, while the sum is 38.

The square root of 821317925 is about 28658.6448563082. The cubic root of 821317925 is about 936.4913430262.

The spelling of 821317925 in words is "eight hundred twenty-one million, three hundred seventeen thousand, nine hundred twenty-five".