264521 has 4 divisors (see below), whose sum is σ = 267792. Its totient is φ = 261252.

The previous prime is 264487. The next prime is 264527. The reversal of 264521 is 125462.

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: 125462 = 2 ⋅62731.

It is a cyclic number.

It is not a de Polignac number, because 264521 - 2¹⁴ = 248137 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 264493 and 264502.

It is not an unprimeable number, because it can be changed into a prime (264527) 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, 1511 + ... + 1676.

It is an arithmetic number, because the mean of its divisors is an integer number (66948).

2²⁶⁴⁵²¹ is an apocalyptic number.

It is an amenable number.

264521 is a deficient number, since it is larger than the sum of its proper divisors (3271).

264521 is an equidigital number, since it uses as much as digits as its factorization.

264521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3270.

The product of its digits is 480, while the sum is 20.

The square root of 264521 is about 514.3160506926. The cubic root of 264521 is about 64.1928590059.

Multiplying 264521 by its product of digits (480), we get a triangular number (126970080 = T₁₅₉₃₅).

Adding to 264521 its reverse (125462), we get a palindrome (389983).

The spelling of 264521 in words is "two hundred sixty-four thousand, five hundred twenty-one".