825857640 has 64 divisors (see below), whose sum is σ = 2752862400. Its totient is φ = 220228416.

The previous prime is 825857623. The next prime is 825857651. The reversal of 825857640 is 46758528.

825857640 is a `hidden beast` number, since 8 + 2 + 585 + 7 + 64 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 381262 + ... + 383421.

It is an arithmetic number, because the mean of its divisors is an integer number (43013475).

Almost surely, 2^825857640 is an apocalyptic number.

It is an amenable number.

825857640 is an abundant number, since it is smaller than the sum of its proper divisors (1927004760).

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

825857640 is a wasteful number, since it uses less digits than its factorization.

825857640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 764703 (or 764693 counting only the distinct ones).

The product of its (nonzero) digits is 537600, while the sum is 45.

The square root of 825857640 is about 28737.7389507247. The cubic root of 825857640 is about 938.2136134684.

The spelling of 825857640 in words is "eight hundred twenty-five million, eight hundred fifty-seven thousand, six hundred forty".