661065 has 8 divisors (see below), whose sum is σ = 1057728. Its totient is φ = 352560.

The previous prime is 661061. The next prime is 661091. The reversal of 661065 is 560166.

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

It is not a de Polignac number, because 661065 - 2² = 661061 is a prime.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (661061) 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, 22021 + ... + 22050.

It is an arithmetic number, because the mean of its divisors is an integer number (132216).

2⁶⁶¹⁰⁶⁵ is an apocalyptic number.

It is an amenable number.

661065 is a deficient number, since it is larger than the sum of its proper divisors (396663).

661065 is a wasteful number, since it uses less digits than its factorization.

661065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44079.

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 661065 is about 813.0590384468. The cubic root of 661065 is about 87.1126826333.

The spelling of 661065 in words is "six hundred sixty-one thousand, sixty-five".