8166640 has 80 divisors (see below), whose sum is σ = 20355840. Its totient is φ = 3041280.

The previous prime is 8166601. The next prime is 8166649. The reversal of 8166640 is 466618.

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 (31).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8166649) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 91716 + ... + 91804.

It is an arithmetic number, because the mean of its divisors is an integer number (254448).

Almost surely, 2^8166640 is an apocalyptic number.

8166640 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 8166640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10177920).

8166640 is an abundant number, since it is smaller than the sum of its proper divisors (12189200).

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

8166640 is a wasteful number, since it uses less digits than its factorization.

8166640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170 (or 164 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 8166640 is about 2857.7333675485. The cubic root of 8166640 is about 201.3791347440.

The spelling of 8166640 in words is "eight million, one hundred sixty-six thousand, six hundred forty".