8400240 has 80 divisors (see below), whose sum is σ = 28941600. Its totient is φ = 2239488.

The previous prime is 8400233. The next prime is 8400247. The reversal of 8400240 is 420048.

It is a happy number.

8400240 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (8400233) and next prime (8400247).

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8400247) 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, 216 + ... + 4104.

It is an arithmetic number, because the mean of its divisors is an integer number (361770).

Almost surely, 2^8400240 is an apocalyptic number.

8400240 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 8400240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14470800).

8400240 is an abundant number, since it is smaller than the sum of its proper divisors (20541360).

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

8400240 is a wasteful number, since it uses less digits than its factorization.

8400240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3911 (or 3899 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 8400240 is about 2898.3167528757. The cubic root of 8400240 is about 203.2812073376.

Adding to 8400240 its reverse (420048), we get a palindrome (8820288).

The spelling of 8400240 in words is "eight million, four hundred thousand, two hundred forty".