840720 has 80 divisors (see below), whose sum is σ = 2714112. Its totient is φ = 215040.

The previous prime is 840713. The next prime is 840727. The reversal of 840720 is 27048.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (840713) and next prime (840727).

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

It is a plaindrome in base 13.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 840720.

It is not an unprimeable number, because it can be changed into a prime (840727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7384 + ... + 7496.

2⁸⁴⁰⁷²⁰ is an apocalyptic number.

840720 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 840720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1357056).

840720 is an abundant number, since it is smaller than the sum of its proper divisors (1873392).

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

840720 is a wasteful number, since it uses less digits than its factorization.

840720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160 (or 154 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 21.

The square root of 840720 is about 916.9078470599. The cubic root of 840720 is about 94.3808301590.

Adding to 840720 its reverse (27048), we get a palindrome (867768).

The spelling of 840720 in words is "eight hundred forty thousand, seven hundred twenty".