264111561 has 48 divisors (see below), whose sum is σ = 450043776. Its totient is φ = 146135808.

The previous prime is 264111557. The next prime is 264111563. The reversal of 264111561 is 165111462.

264111561 is a `hidden beast` number, since 2 + 641 + 1 + 15 + 6 + 1 = 666.

It is not a de Polignac number, because 264111561 - 2² = 264111557 is a prime.

It is not an unprimeable number, because it can be changed into a prime (264111563) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 276661 + ... + 277613.

It is an arithmetic number, because the mean of its divisors is an integer number (9375912).

Almost surely, 2^264111561 is an apocalyptic number.

264111561 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

264111561 is a deficient number, since it is larger than the sum of its proper divisors (185932215).

264111561 is a wasteful number, since it uses less digits than its factorization.

264111561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1102 (or 1099 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 264111561 is about 16251.5094991204. The cubic root of 264111561 is about 641.5972158336.

Subtracting from 264111561 its reverse (165111462), we obtain a palindrome (99000099).

It can be divided in two parts, 26411 and 1561, that added together give a palindrome (27972).

The spelling of 264111561 in words is "two hundred sixty-four million, one hundred eleven thousand, five hundred sixty-one".