261111729947 has 2 divisors, whose sum is σ = 261111729948. Its totient is φ = 261111729946.

The previous prime is 261111729941. The next prime is 261111729973. The reversal of 261111729947 is 749927111162.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261111729947 - 2⁶ = 261111729883 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261111729895 and 261111729904.

It is not a weakly prime, because it can be changed into another prime (261111729941) 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 as a sum of consecutive naturals, namely, 130555864973 + 130555864974.

It is an arithmetic number, because the mean of its divisors is an integer number (130555864974).

Almost surely, 2^261111729947 is an apocalyptic number.

261111729947 is a deficient number, since it is larger than the sum of its proper divisors (1).

261111729947 is an equidigital number, since it uses as much as digits as its factorization.

261111729947 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 381024, while the sum is 50.

The spelling of 261111729947 in words is "two hundred sixty-one billion, one hundred eleven million, seven hundred twenty-nine thousand, nine hundred forty-seven".