261520016507 has 8 divisors (see below), whose sum is σ = 267886299120. Its totient is φ = 255166662240.

The previous prime is 261520016447. The next prime is 261520016533. The reversal of 261520016507 is 705610025162.

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

It is a cyclic number.

It is not a de Polignac number, because 261520016507 - 2²⁶ = 261452907643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261520015507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3191132 + ... + 3272057.

It is an arithmetic number, because the mean of its divisors is an integer number (33485787390).

Almost surely, 2^261520016507 is an apocalyptic number.

261520016507 is a deficient number, since it is larger than the sum of its proper divisors (6366282613).

261520016507 is an equidigital number, since it uses as much as digits as its factorization.

261520016507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6464173.

The product of its (nonzero) digits is 25200, while the sum is 35.

The spelling of 261520016507 in words is "two hundred sixty-one billion, five hundred twenty million, sixteen thousand, five hundred seven".