264640521 has 16 divisors (see below), whose sum is σ = 368340480. Its totient is φ = 168812160.

The previous prime is 264640517. The next prime is 264640529. The reversal of 264640521 is 125046462.

It is not a de Polignac number, because 264640521 - 2² = 264640517 is a prime.

It is not an unprimeable number, because it can be changed into a prime (264640529) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7710 + ... + 24263.

It is an arithmetic number, because the mean of its divisors is an integer number (23021280).

Almost surely, 2^264640521 is an apocalyptic number.

It is an amenable number.

264640521 is a deficient number, since it is larger than the sum of its proper divisors (103699959).

264640521 is a wasteful number, since it uses less digits than its factorization.

264640521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32096.

The product of its (nonzero) digits is 11520, while the sum is 30.

The square root of 264640521 is about 16267.7755393907. The cubic root of 264640521 is about 642.0252583690.

Adding to 264640521 its reverse (125046462), we get a palindrome (389686983).

The spelling of 264640521 in words is "two hundred sixty-four million, six hundred forty thousand, five hundred twenty-one".