261534370137043 has 4 divisors (see below), whose sum is σ = 261655394836168. Its totient is φ = 261413345437920.

The previous prime is 261534370136989. The next prime is 261534370137101. The reversal of 261534370137043 is 340731073435162.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 261534370137043 - 2⁹ = 261534370136531 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261534370137343) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 60512346321 + ... + 60512350642.

It is an arithmetic number, because the mean of its divisors is an integer number (65413848709042).

Almost surely, 2^{261534370137043} is an apocalyptic number.

261534370137043 is a deficient number, since it is larger than the sum of its proper divisors (121024699125).

261534370137043 is a wasteful number, since it uses less digits than its factorization.

261534370137043 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121024699124.

The product of its (nonzero) digits is 3810240, while the sum is 49.

The spelling of 261534370137043 in words is "two hundred sixty-one trillion, five hundred thirty-four billion, three hundred seventy million, one hundred thirty-seven thousand, forty-three".