264740721 has 16 divisors (see below), whose sum is σ = 404713344. Its totient is φ = 150793344.

The previous prime is 264740719. The next prime is 264740743. The reversal of 264740721 is 127047462.

It is not a de Polignac number, because 264740721 - 2¹ = 264740719 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (264740761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13566 + ... + 26711.

It is an arithmetic number, because the mean of its divisors is an integer number (25294584).

Almost surely, 2^264740721 is an apocalyptic number.

264740721 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

264740721 is a deficient number, since it is larger than the sum of its proper divisors (139972623).

264740721 is a wasteful number, since it uses less digits than its factorization.

264740721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40600.

The product of its (nonzero) digits is 18816, while the sum is 33.

The square root of 264740721 is about 16270.8549560249. The cubic root of 264740721 is about 642.1062774727.

The spelling of 264740721 in words is "two hundred sixty-four million, seven hundred forty thousand, seven hundred twenty-one".