264581491 has 4 divisors (see below), whose sum is σ = 264616984. Its totient is φ = 264546000.

The previous prime is 264581467. The next prime is 264581509. The reversal of 264581491 is 194185462.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 264581491 - 2⁷ = 264581363 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (264581411) 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, 1770 + ... + 23071.

It is an arithmetic number, because the mean of its divisors is an integer number (66154246).

Almost surely, 2^264581491 is an apocalyptic number.

264581491 is a deficient number, since it is larger than the sum of its proper divisors (35493).

264581491 is a wasteful number, since it uses less digits than its factorization.

264581491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35492.

The product of its digits is 69120, while the sum is 40.

The square root of 264581491 is about 16265.9611151632. The cubic root of 264581491 is about 641.9775186791.

The spelling of 264581491 in words is "two hundred sixty-four million, five hundred eighty-one thousand, four hundred ninety-one".