8291840 has 80 divisors (see below), whose sum is σ = 20623680. Its totient is φ = 3194880.

The previous prime is 8291839. The next prime is 8291879. The reversal of 8291840 is 481928.

It is a happy number.

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

It is a super-2 number, since 2×8291840² = 137509221171200, which contains 22 as substring.

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 = 8291797 and 8291806.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 104921 + ... + 104999.

It is an arithmetic number, because the mean of its divisors is an integer number (257796).

Almost surely, 2^8291840 is an apocalyptic number.

8291840 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 8291840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10311840).

8291840 is an abundant number, since it is smaller than the sum of its proper divisors (12331840).

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

8291840 is an equidigital number, since it uses as much as digits as its factorization.

8291840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143 (or 127 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 32.

The square root of 8291840 is about 2879.5555212567. Note that the first 4 decimals coincide. The cubic root of 8291840 is about 202.4030120316.

The spelling of 8291840 in words is "eight million, two hundred ninety-one thousand, eight hundred forty".