264626907561 has 9 divisors (see below), whose sum is σ = 382241095639. Its totient is φ = 176416909536.

The previous prime is 264626907541. The next prime is 264626907593. The reversal of 264626907561 is 165709626462.

The square root of 264626907561 is 514419.

It is a perfect power (a square), and thus also a powerful number.

264626907561 is a `hidden beast` number, since 2 + 6 + 4 + 626 + 9 + 0 + 7 + 5 + 6 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 36662675625 + 227964231936 = 191475^2 + 477456^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 264626907561 - 2¹⁵ = 264626874793 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 264626907498 and 264626907507.

It is not an unprimeable number, because it can be changed into a prime (264626907511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1457521 + ... + 1628993.

Almost surely, 2^264626907561 is an apocalyptic number.

264626907561 is the 514419-th square number.

264626907561 is the 257210-th centered octagonal number.

It is an amenable number.

264626907561 is a deficient number, since it is larger than the sum of its proper divisors (117614188078).

264626907561 is an frugal number, since it uses more digits than its factorization.

264626907561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342952 (or 171476 counting only the distinct ones).

The product of its (nonzero) digits is 6531840, while the sum is 54.

The spelling of 264626907561 in words is "two hundred sixty-four billion, six hundred twenty-six million, nine hundred seven thousand, five hundred sixty-one".