8191618 has 8 divisors (see below), whose sum is σ = 12336012. Its totient is φ = 4079616.

The previous prime is 8191613. The next prime is 8191633. The reversal of 8191618 is 8161918.

It can be written as a sum of positive squares in 2 ways, for example, as 6744409 + 1447209 = 2597^2 + 1203^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

8191618 is a strobogrammatic number because it is the same when read upside-down.

It is not an unprimeable number, because it can be changed into a prime (8191613) 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, 7455 + ... + 8482.

Almost surely, 2^8191618 is an apocalyptic number.

8191618 is a deficient number, since it is larger than the sum of its proper divisors (4144394).

8191618 is a wasteful number, since it uses less digits than its factorization.

8191618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16196.

The product of its digits is 3456, while the sum is 34.

The square root of 8191618 is about 2862.1002777681. The cubic root of 8191618 is about 201.5842345371.

The spelling of 8191618 in words is "eight million, one hundred ninety-one thousand, six hundred eighteen".