261587803 has 4 divisors (see below), whose sum is σ = 261682408. Its totient is φ = 261493200.

The previous prime is 261587797. The next prime is 261587813. The reversal of 261587803 is 308785162.

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 261587803 - 2⁵ = 261587771 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261587813) 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 in 3 ways as a sum of consecutive naturals, for example, 43026 + ... + 48727.

It is an arithmetic number, because the mean of its divisors is an integer number (65420602).

Almost surely, 2^261587803 is an apocalyptic number.

261587803 is a deficient number, since it is larger than the sum of its proper divisors (94605).

261587803 is an equidigital number, since it uses as much as digits as its factorization.

261587803 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94604.

The product of its (nonzero) digits is 80640, while the sum is 40.

The square root of 261587803 is about 16173.6762364034. The cubic root of 261587803 is about 639.5470452232.

The spelling of 261587803 in words is "two hundred sixty-one million, five hundred eighty-seven thousand, eight hundred three".