84381440 has 144 divisors (see below), whose sum is σ = 237970656. Its totient is φ = 28262400.

The previous prime is 84381433. The next prime is 84381443. The reversal of 84381440 is 4418348.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 84381397 and 84381406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84381443) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 182810 + ... + 183270.

It is an arithmetic number, because the mean of its divisors is an integer number (1652574).

Almost surely, 2^84381440 is an apocalyptic number.

84381440 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 84381440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118985328).

84381440 is an abundant number, since it is smaller than the sum of its proper divisors (153589216).

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

84381440 is a wasteful number, since it uses less digits than its factorization.

84381440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 506 (or 492 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 32.

The square root of 84381440 is about 9185.9370779469. The cubic root of 84381440 is about 438.6138193661.

Adding to 84381440 its reverse (4418348), we get a palindrome (88799788).

The spelling of 84381440 in words is "eighty-four million, three hundred eighty-one thousand, four hundred forty".