828685440 has 576 divisors, whose sum is σ = 3333166200. Its totient is φ = 189235200.

The previous prime is 828685439. The next prime is 828685447. The reversal of 828685440 is 44586828.

It can be written as a sum of positive squares in 4 ways, for example, as 457275456 + 371409984 = 21384^2 + 19272^2 .

It is a tau number, because it is divible by the number of its divisors (576).

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

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

It is not an unprimeable number, because it can be changed into a prime (828685447) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 20211820 + ... + 20211860.

Almost surely, 2^828685440 is an apocalyptic number.

828685440 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 828685440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1666583100).

828685440 is an abundant number, since it is smaller than the sum of its proper divisors (2504480760).

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

828685440 is a wasteful number, since it uses less digits than its factorization.

828685440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117 (or 91 counting only the distinct ones).

The product of its (nonzero) digits is 491520, while the sum is 45.

The square root of 828685440 is about 28786.8970193038. The cubic root of 828685440 is about 939.2832320717.

The spelling of 828685440 in words is "eight hundred twenty-eight million, six hundred eighty-five thousand, four hundred forty".