8199661 has 16 divisors (see below), whose sum is σ = 9224064. Its totient is φ = 7248384.

The previous prime is 8199649. The next prime is 8199673. The reversal of 8199661 is 1669918.

It is an interprime number because it is at equal distance from previous prime (8199649) and next prime (8199673).

It is a cyclic number.

It is not a de Polignac number, because 8199661 - 2⁵ = 8199629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8199641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26041 + ... + 26353.

It is an arithmetic number, because the mean of its divisors is an integer number (576504).

Almost surely, 2^8199661 is an apocalyptic number.

It is an amenable number.

8199661 is a deficient number, since it is larger than the sum of its proper divisors (1024403).

8199661 is a wasteful number, since it uses less digits than its factorization.

8199661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420.

The product of its digits is 23328, while the sum is 40.

The square root of 8199661 is about 2863.5050200759. The cubic root of 8199661 is about 201.6501886073.

The spelling of 8199661 in words is "eight million, one hundred ninety-nine thousand, six hundred sixty-one".