8191640 has 16 divisors (see below), whose sum is σ = 18431280. Its totient is φ = 3276640.

The previous prime is 8191639. The next prime is 8191643. The reversal of 8191640 is 461918.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8191643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 102356 + ... + 102435.

It is an arithmetic number, because the mean of its divisors is an integer number (1151955).

Almost surely, 2^8191640 is an apocalyptic number.

It is an amenable number.

8191640 is an abundant number, since it is smaller than the sum of its proper divisors (10239640).

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

8191640 is a wasteful number, since it uses less digits than its factorization.

8191640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204802 (or 204798 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 8191640 is about 2862.1041210969. The cubic root of 8191640 is about 201.5844150000.

The spelling of 8191640 in words is "eight million, one hundred ninety-one thousand, six hundred forty".