261123272873 has 4 divisors (see below), whose sum is σ = 269546604288. Its totient is φ = 252699941460.

The previous prime is 261123272807. The next prime is 261123272887. The reversal of 261123272873 is 378272321162.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 378272321162 = 2 ⋅189136160581.

It is a cyclic number.

It is not a de Polignac number, because 261123272873 - 2¹⁴ = 261123256489 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (261123272803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4211665661 + ... + 4211665722.

It is an arithmetic number, because the mean of its divisors is an integer number (67386651072).

Almost surely, 2^261123272873 is an apocalyptic number.

It is an amenable number.

261123272873 is a deficient number, since it is larger than the sum of its proper divisors (8423331415).

261123272873 is an equidigital number, since it uses as much as digits as its factorization.

261123272873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8423331414.

The product of its digits is 338688, while the sum is 44.

The spelling of 261123272873 in words is "two hundred sixty-one billion, one hundred twenty-three million, two hundred seventy-two thousand, eight hundred seventy-three".