261564252542303 has 4 divisors (see below), whose sum is σ = 261765301162008. Its totient is φ = 261363203922600.

The previous prime is 261564252542273. The next prime is 261564252542309. The reversal of 261564252542303 is 303245252465162.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 261564252542303 - 2³⁰ = 261563178800479 is a prime.

It is a super-2 number, since 2×261564252542303² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261564252542309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 100524307901 + ... + 100524310502.

It is an arithmetic number, because the mean of its divisors is an integer number (65441325290502).

Almost surely, 2^{261564252542303} is an apocalyptic number.

261564252542303 is a deficient number, since it is larger than the sum of its proper divisors (201048619705).

261564252542303 is a wasteful number, since it uses less digits than its factorization.

261564252542303 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201048619704.

The product of its (nonzero) digits is 10368000, while the sum is 50.

The spelling of 261564252542303 in words is "two hundred sixty-one trillion, five hundred sixty-four billion, two hundred fifty-two million, five hundred forty-two thousand, three hundred three".