9665661 has 16 divisors (see below), whose sum is σ = 13667840. Its totient is φ = 6058800.

The previous prime is 9665657. The next prime is 9665701. The reversal of 9665661 is 1665669.

It is not a de Polignac number, because 9665661 - 2² = 9665657 is a prime.

Its product of digits (58320) is a multiple of the sum of its prime divisors (1296).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9665641) 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, 8046 + ... + 9168.

It is an arithmetic number, because the mean of its divisors is an integer number (854240).

Almost surely, 2^9665661 is an apocalyptic number.

It is an amenable number.

9665661 is a deficient number, since it is larger than the sum of its proper divisors (4002179).

9665661 is a wasteful number, since it uses less digits than its factorization.

9665661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1296.

The product of its digits is 58320, while the sum is 39.

The square root of 9665661 is about 3108.9646186472. The cubic root of 9665661 is about 213.0151634602.

The spelling of 9665661 in words is "nine million, six hundred sixty-five thousand, six hundred sixty-one".