825855921 has 12 divisors (see below), whose sum is σ = 1301348880. Its totient is φ = 500518680.

The previous prime is 825855887. The next prime is 825855931. The reversal of 825855921 is 129558528.

It is a happy number.

825855921 is a `hidden beast` number, since 8 + 2 + 58 + 5 + 592 + 1 = 666.

It is not a de Polignac number, because 825855921 - 2⁶ = 825855857 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (825855931) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4170891 + ... + 4171088.

It is an arithmetic number, because the mean of its divisors is an integer number (108445740).

Almost surely, 2^825855921 is an apocalyptic number.

It is an amenable number.

825855921 is a deficient number, since it is larger than the sum of its proper divisors (475492959).

825855921 is a wasteful number, since it uses less digits than its factorization.

825855921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8341996 (or 8341993 counting only the distinct ones).

The product of its digits is 288000, while the sum is 45.

The square root of 825855921 is about 28737.7090423019. The cubic root of 825855921 is about 938.2129625126.

The spelling of 825855921 in words is "eight hundred twenty-five million, eight hundred fifty-five thousand, nine hundred twenty-one".