67521 has 8 divisors (see below), whose sum is σ = 91584. Its totient is φ = 44240.

The previous prime is 67511. The next prime is 67523. The reversal of 67521 is 12576.

67521 = T₃ + T₄ + ... + T₇₃.

67521 is nontrivially palindromic in base 2.

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 67521 - 2⁵ = 67489 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (67523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55 + ... + 371.

It is an arithmetic number, because the mean of its divisors is an integer number (11448).

2⁶⁷⁵²¹ is an apocalyptic number.

It is an amenable number.

67521 is a deficient number, since it is larger than the sum of its proper divisors (24063).

67521 is a wasteful number, since it uses less digits than its factorization.

67521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391.

The product of its digits is 420, while the sum is 21.

The square root of 67521 is about 259.8480325113. The cubic root of 67521 is about 40.7204862385.

Subtracting from 67521 its reverse (12576), we obtain a palindrome (54945).

It can be divided in two parts, 675 and 21, that added together give a palindrome (696).

The spelling of 67521 in words is "sixty-seven thousand, five hundred twenty-one".