264135681 has 32 divisors (see below), whose sum is σ = 420059520. Its totient is φ = 163441152.

The previous prime is 264135679. The next prime is 264135689. The reversal of 264135681 is 186531462.

It is a happy number.

264135681 is a `hidden beast` number, since 2 + 641 + 3 + 5 + 6 + 8 + 1 = 666.

264135681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 264135681 - 2¹ = 264135679 is a prime.

It is a super-2 number, since 2×264135681² = 139535315954667522, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (264135689) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 29566 + ... + 37448.

It is an arithmetic number, because the mean of its divisors is an integer number (13126860).

Almost surely, 2^264135681 is an apocalyptic number.

It is an amenable number.

264135681 is a deficient number, since it is larger than the sum of its proper divisors (155923839).

264135681 is a wasteful number, since it uses less digits than its factorization.

264135681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7982 (or 7976 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 264135681 is about 16252.2515670906. The cubic root of 264135681 is about 641.6167465372.

The spelling of 264135681 in words is "two hundred sixty-four million, one hundred thirty-five thousand, six hundred eighty-one".