261734887 has 2 divisors, whose sum is σ = 261734888. Its totient is φ = 261734886.

The previous prime is 261734881. The next prime is 261734909. The reversal of 261734887 is 788437162.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261734887 is a prime.

It is a zygodrome in base 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261734881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130867443 + 130867444.

It is an arithmetic number, because the mean of its divisors is an integer number (130867444).

Almost surely, 2^261734887 is an apocalyptic number.

261734887 is a deficient number, since it is larger than the sum of its proper divisors (1).

261734887 is an equidigital number, since it uses as much as digits as its factorization.

261734887 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 451584, while the sum is 46.

The square root of 261734887 is about 16178.2226156027. Note that the first 3 decimals coincide. The cubic root of 261734887 is about 639.6668896394. Note that the first 3 decimals are identical.

The spelling of 261734887 in words is "two hundred sixty-one million, seven hundred thirty-four thousand, eight hundred eighty-seven".