261358956085 has 32 divisors (see below), whose sum is σ = 329221791360. Its totient is φ = 198998092800.

The previous prime is 261358956043. The next prime is 261358956101. The reversal of 261358956085 is 580659853162.

It is not a de Polignac number, because 261358956085 - 2¹⁹ = 261358431797 is a prime.

It is a super-3 number, since 3×261358956085³ (a number of 35 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1501969 + ... + 1666921.

It is an arithmetic number, because the mean of its divisors is an integer number (10288180980).

Almost surely, 2^261358956085 is an apocalyptic number.

It is an amenable number.

261358956085 is a deficient number, since it is larger than the sum of its proper divisors (67862835275).

261358956085 is a wasteful number, since it uses less digits than its factorization.

261358956085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165189.

The product of its (nonzero) digits is 15552000, while the sum is 58.

The spelling of 261358956085 in words is "two hundred sixty-one billion, three hundred fifty-eight million, nine hundred fifty-six thousand, eighty-five".