261560993803 has 4 divisors (see below), whose sum is σ = 269998445248. Its totient is φ = 253123542360.

The previous prime is 261560993791. The next prime is 261560993851. The reversal of 261560993803 is 308399065162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 308399065162 = 2 ⋅154199532581.

It is not a de Polignac number, because 261560993803 - 2¹³ = 261560985611 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261560993303) 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, 4218725676 + ... + 4218725737.

It is an arithmetic number, because the mean of its divisors is an integer number (67499611312).

Almost surely, 2^261560993803 is an apocalyptic number.

261560993803 is a deficient number, since it is larger than the sum of its proper divisors (8437451445).

261560993803 is an equidigital number, since it uses as much as digits as its factorization.

261560993803 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8437451444.

The product of its (nonzero) digits is 2099520, while the sum is 52.

The spelling of 261560993803 in words is "two hundred sixty-one billion, five hundred sixty million, nine hundred ninety-three thousand, eight hundred three".