261590887 has 8 divisors (see below), whose sum is σ = 269723520. Its totient is φ = 253551480.

The previous prime is 261590869. The next prime is 261590893. The reversal of 261590887 is 788095162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261590887 - 2¹¹ = 261588839 is a prime.

It is a super-2 number, since 2×261590887² = 136859584322893538, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261590867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17587 + ... + 28852.

It is an arithmetic number, because the mean of its divisors is an integer number (33715440).

Almost surely, 2^261590887 is an apocalyptic number.

261590887 is a deficient number, since it is larger than the sum of its proper divisors (8132633).

261590887 is a wasteful number, since it uses less digits than its factorization.

261590887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46613.

The product of its (nonzero) digits is 241920, while the sum is 46.

The square root of 261590887 is about 16173.7715762280. The cubic root of 261590887 is about 639.5495585353.

The spelling of 261590887 in words is "two hundred sixty-one million, five hundred ninety thousand, eight hundred eighty-seven".