6661523 has 4 divisors (see below), whose sum is σ = 7267128. Its totient is φ = 6055920.

The previous prime is 6661511. The next prime is 6661547. The reversal of 6661523 is 3251666.

6661523 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 6661523 - 2¹⁰ = 6660499 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6661553) 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, 302786 + ... + 302807.

It is an arithmetic number, because the mean of its divisors is an integer number (1816782).

Almost surely, 2^6661523 is an apocalyptic number.

6661523 is a deficient number, since it is larger than the sum of its proper divisors (605605).

6661523 is a wasteful number, since it uses less digits than its factorization.

6661523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 605604.

The product of its digits is 6480, while the sum is 29.

The square root of 6661523 is about 2580.9926385017. The cubic root of 6661523 is about 188.1587895657.

The spelling of 6661523 in words is "six million, six hundred sixty-one thousand, five hundred twenty-three".