261564210310345 has 16 divisors (see below), whose sum is σ = 344761979725440. Its totient is φ = 189619088845824.

The previous prime is 261564210310313. The next prime is 261564210310387. The reversal of 261564210310345 is 543013012465162.

It is not a de Polignac number, because 261564210310345 - 2⁵ = 261564210310313 is a prime.

It is a super-2 number, since 2×261564210310345² (a number of 30 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59854508184 + ... + 59854512553.

It is an arithmetic number, because the mean of its divisors is an integer number (21547623732840).

Almost surely, 2^{261564210310345} is an apocalyptic number.

It is an amenable number.

261564210310345 is a deficient number, since it is larger than the sum of its proper divisors (83197769415095).

261564210310345 is a wasteful number, since it uses less digits than its factorization.

261564210310345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119709020784.

The product of its (nonzero) digits is 518400, while the sum is 43.

The spelling of 261564210310345 in words is "two hundred sixty-one trillion, five hundred sixty-four billion, two hundred ten million, three hundred ten thousand, three hundred forty-five".