264120561 has 16 divisors (see below), whose sum is σ = 393264000. Its totient is φ = 175191984.

The previous prime is 264120559. The next prime is 264120599. The reversal of 264120561 is 165021462.

It is not a de Polignac number, because 264120561 - 2¹ = 264120559 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (264120511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19206 + ... + 29951.

It is an arithmetic number, because the mean of its divisors is an integer number (24579000).

Almost surely, 2^264120561 is an apocalyptic number.

It is an amenable number.

264120561 is a deficient number, since it is larger than the sum of its proper divisors (129143439).

264120561 is a wasteful number, since it uses less digits than its factorization.

264120561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49365 (or 49359 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 264120561 is about 16251.7863941168. The cubic root of 264120561 is about 641.6045035486.

Subtracting from 264120561 its reverse (165021462), we obtain a palindrome (99099099).

The spelling of 264120561 in words is "two hundred sixty-four million, one hundred twenty thousand, five hundred sixty-one".