261445025535 has 16 divisors (see below), whose sum is σ = 418395840000. Its totient is φ = 139409413920.

The previous prime is 261445025489. The next prime is 261445025551. The reversal of 261445025535 is 535520544162.

It is not a de Polignac number, because 261445025535 - 2¹⁴ = 261445009151 is a prime.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 1668331 + ... + 1818300.

It is an arithmetic number, because the mean of its divisors is an integer number (26149740000).

Almost surely, 2^261445025535 is an apocalyptic number.

261445025535 is a deficient number, since it is larger than the sum of its proper divisors (156950814465).

261445025535 is a wasteful number, since it uses less digits than its factorization.

261445025535 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3491638.

The product of its (nonzero) digits is 720000, while the sum is 42.

Adding to 261445025535 its reverse (535520544162), we get a palindrome (796965569697).

The spelling of 261445025535 in words is "two hundred sixty-one billion, four hundred forty-five million, twenty-five thousand, five hundred thirty-five".