291655 has 16 divisors (see below), whose sum is σ = 431424. Its totient is φ = 184320.

The previous prime is 291649. The next prime is 291661. The reversal of 291655 is 556192.

291655 is an esthetic number in base 7, because in such base its adjacent digits differ by 1.

It is an interprime number because it is at equal distance from previous prime (291649) and next prime (291661).

It is not a de Polignac number, because 291655 - 2³ = 291647 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 135 + ... + 775.

It is an arithmetic number, because the mean of its divisors is an integer number (26964).

2²⁹¹⁶⁵⁵ is an apocalyptic number.

291655 is a deficient number, since it is larger than the sum of its proper divisors (139769).

291655 is a wasteful number, since it uses less digits than its factorization.

291655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 666.

The product of its digits is 2700, while the sum is 28.

The square root of 291655 is about 540.0509235248. The cubic root of 291655 is about 66.3167358849.

It can be divided in two parts, 291 and 655, that added together give a triangular number (946 = T₄₃).

The spelling of 291655 in words is "two hundred ninety-one thousand, six hundred fifty-five".