266991487 has 8 divisors (see below), whose sum is σ = 315655200. Its totient is φ = 220958304.

The previous prime is 266991479. The next prime is 266991509. The reversal of 266991487 is 784199662.

It is a happy number.

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

It is not a de Polignac number, because 266991487 - 2³ = 266991479 is a prime.

It is a super-3 number, since 3×266991487³ (a number of 26 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (266991407) 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 in 7 ways as a sum of consecutive naturals, for example, 657412 + ... + 657817.

It is an arithmetic number, because the mean of its divisors is an integer number (39456900).

Almost surely, 2^266991487 is an apocalyptic number.

266991487 is a deficient number, since it is larger than the sum of its proper divisors (48663713).

266991487 is a wasteful number, since it uses less digits than its factorization.

266991487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1315265.

The product of its digits is 1306368, while the sum is 52.

The square root of 266991487 is about 16339.8741427222. The cubic root of 266991487 is about 643.9208258504.

The spelling of 266991487 in words is "two hundred sixty-six million, nine hundred ninety-one thousand, four hundred eighty-seven".