84400440 has 128 divisors (see below), whose sum is σ = 266112000. Its totient is φ = 21385728.

The previous prime is 84400439. The next prime is 84400471. The reversal of 84400440 is 4400448.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 84400440.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 274767 + ... + 275073.

It is an arithmetic number, because the mean of its divisors is an integer number (2079000).

Almost surely, 2^84400440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 84400440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (133056000).

84400440 is an abundant number, since it is smaller than the sum of its proper divisors (181711560).

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

84400440 is a wasteful number, since it uses less digits than its factorization.

84400440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 429 (or 425 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 24.

The square root of 84400440 is about 9186.9712092724. The cubic root of 84400440 is about 438.6467374942.

Adding to 84400440 its reverse (4400448), we get a palindrome (88800888).

The spelling of 84400440 in words is "eighty-four million, four hundred thousand, four hundred forty".