825869520 has 630 divisors, whose sum is σ = 3557511702. Its totient is φ = 177666048.

The previous prime is 825869467. The next prime is 825869521. The reversal of 825869520 is 25968528.

It can be written as a sum of positive squares in 3 ways, for example, as 276623424 + 549246096 = 16632^2 + 23436^2 .

It is a tau number, because it is divible by the number of its divisors (630).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (825869521) 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 125 ways as a sum of consecutive naturals, for example, 48580552 + ... + 48580568.

Almost surely, 2^825869520 is an apocalyptic number.

825869520 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 825869520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1778755851).

825869520 is an abundant number, since it is smaller than the sum of its proper divisors (2731642182).

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

825869520 is a wasteful number, since it uses less digits than its factorization.

825869520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79 (or 34 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 45.

The square root of 825869520 is about 28737.9456468273. The cubic root of 825869520 is about 938.2181121954.

Multiplying 825869520 by its sum of digits (45), we get a square (37164128400 = 192780²).

825869520 divided by its sum of digits (45) gives a square (18352656 = 4284²).

The spelling of 825869520 in words is "eight hundred twenty-five million, eight hundred sixty-nine thousand, five hundred twenty".