7665661 has 4 divisors (see below), whose sum is σ = 7695072. Its totient is φ = 7636252.

The previous prime is 7665641. The next prime is 7665667. The reversal of 7665661 is 1665667.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1665667 = 383 ⋅4349.

It is a cyclic number.

It is not a de Polignac number, because 7665661 - 2⁷ = 7665533 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 7665661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7665667) 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, 14311 + ... + 14836.

It is an arithmetic number, because the mean of its divisors is an integer number (1923768).

Almost surely, 2^7665661 is an apocalyptic number.

It is an amenable number.

7665661 is a deficient number, since it is larger than the sum of its proper divisors (29411).

7665661 is a wasteful number, since it uses less digits than its factorization.

7665661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29410.

The product of its digits is 45360, while the sum is 37.

The square root of 7665661 is about 2768.6930129576. The cubic root of 7665661 is about 197.1741012032.

The spelling of 7665661 in words is "seven million, six hundred sixty-five thousand, six hundred sixty-one".