6601521 has 8 divisors (see below), whose sum is σ = 8968320. Its totient is φ = 4317872.

The previous prime is 6601519. The next prime is 6601523. The reversal of 6601521 is 1251066.

It is a happy number.

6601521 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (6601519) and next prime (6601523).

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

It is a cyclic number.

It is not a de Polignac number, because 6601521 - 2¹ = 6601519 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6601523) 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, 20601 + ... + 20918.

It is an arithmetic number, because the mean of its divisors is an integer number (1121040).

Almost surely, 2^6601521 is an apocalyptic number.

It is an amenable number.

6601521 is a deficient number, since it is larger than the sum of its proper divisors (2366799).

6601521 is a wasteful number, since it uses less digits than its factorization.

6601521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41575.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 6601521 is about 2569.3425229035. The cubic root of 6601521 is about 187.5921538113.

Subtracting from 6601521 its product of nonzero digits (360), we obtain a triangular number (6601161 = T₃₆₃₃).

Adding to 6601521 its reverse (1251066), we get a palindrome (7852587).

The spelling of 6601521 in words is "six million, six hundred one thousand, five hundred twenty-one".