261499063505 has 8 divisors (see below), whose sum is σ = 313974487872. Its totient is φ = 209082176368.

The previous prime is 261499063459. The next prime is 261499063519. The reversal of 261499063505 is 505360994162.

261499063505 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261499063505 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14624477 + ... + 14642346.

It is an arithmetic number, because the mean of its divisors is an integer number (39246810984).

Almost surely, 2^261499063505 is an apocalyptic number.

It is an amenable number.

261499063505 is a deficient number, since it is larger than the sum of its proper divisors (52475424367).

261499063505 is a wasteful number, since it uses less digits than its factorization.

261499063505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29268615.

The product of its (nonzero) digits is 1749600, while the sum is 50.

The spelling of 261499063505 in words is "two hundred sixty-one billion, four hundred ninety-nine million, sixty-three thousand, five hundred five".