9661665 has 16 divisors (see below), whose sum is σ = 16648128. Its totient is φ = 4756416.

The previous prime is 9661637. The next prime is 9661667. The reversal of 9661665 is 5661669.

9661665 is digitally balanced in base 2, base 3 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 9661665 - 2⁷ = 9661537 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

9661665 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (9661667) 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, 24579 + ... + 24968.

It is an arithmetic number, because the mean of its divisors is an integer number (1040508).

Almost surely, 2^9661665 is an apocalyptic number.

It is an amenable number.

9661665 is a deficient number, since it is larger than the sum of its proper divisors (6986463).

9661665 is a wasteful number, since it uses less digits than its factorization.

9661665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49568.

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

The square root of 9661665 is about 3108.3218945277. The cubic root of 9661665 is about 212.9858043395.

The spelling of 9661665 in words is "nine million, six hundred sixty-one thousand, six hundred sixty-five".