8661601 has 4 divisors (see below), whose sum is σ = 9327892. Its totient is φ = 7995312.

The previous prime is 8661581. The next prime is 8661623. The reversal of 8661601 is 1061668.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4665600 + 3996001 = 2160^2 + 1999^2 .

It is not a de Polignac number, because 8661601 - 2⁹ = 8661089 is a prime.

It is a Duffinian number.

8661601 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 8661601.

It is not an unprimeable number, because it can be changed into a prime (8661641) 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, 333126 + ... + 333151.

It is an arithmetic number, because the mean of its divisors is an integer number (2331973).

Almost surely, 2^8661601 is an apocalyptic number.

It is an amenable number.

8661601 is a deficient number, since it is larger than the sum of its proper divisors (666291).

8661601 is a wasteful number, since it uses less digits than its factorization.

8661601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 666290.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 8661601 is about 2943.0598023146. The cubic root of 8661601 is about 205.3679767988.

The spelling of 8661601 in words is "eight million, six hundred sixty-one thousand, six hundred one".