825423840 has 144 divisors (see below), whose sum is σ = 2965107600. Its totient is φ = 208521216.

The previous prime is 825423827. The next prime is 825423847. The reversal of 825423840 is 48324528.

825423840 is a `hidden beast` number, since 82 + 542 + 38 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 825423795 and 825423804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (825423847) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12276 + ... + 42444.

It is an arithmetic number, because the mean of its divisors is an integer number (20591025).

Almost surely, 2^825423840 is an apocalyptic number.

825423840 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 825423840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1482553800).

825423840 is an abundant number, since it is smaller than the sum of its proper divisors (2139683760).

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

825423840 is a wasteful number, since it uses less digits than its factorization.

825423840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30209 (or 30198 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 36.

The square root of 825423840 is about 28730.1903926862. The cubic root of 825423840 is about 938.0493122103.

The spelling of 825423840 in words is "eight hundred twenty-five million, four hundred twenty-three thousand, eight hundred forty".