8181649 has 8 divisors (see below), whose sum is σ = 9437120. Its totient is φ = 6947856.

The previous prime is 8181637. The next prime is 8181697. The reversal of 8181649 is 9461818.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 8181649 - 2⁵ = 8181617 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8181049) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4599 + ... + 6124.

It is an arithmetic number, because the mean of its divisors is an integer number (1179640).

Almost surely, 2^8181649 is an apocalyptic number.

It is an amenable number.

8181649 is a deficient number, since it is larger than the sum of its proper divisors (1255471).

8181649 is a wasteful number, since it uses less digits than its factorization.

8181649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10839.

The product of its digits is 13824, while the sum is 37.

The square root of 8181649 is about 2860.3581943526. The cubic root of 8181649 is about 201.5024269709.

The spelling of 8181649 in words is "eight million, one hundred eighty-one thousand, six hundred forty-nine".