655091 has 4 divisors (see below), whose sum is σ = 657000. Its totient is φ = 653184.

The previous prime is 655087. The next prime is 655103. The reversal of 655091 is 190556.

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 655091 - 2² = 655087 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 655091.

It is not an unprimeable number, because it can be changed into a prime (655001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 281 + ... + 1178.

It is an arithmetic number, because the mean of its divisors is an integer number (164250).

2⁶⁵⁵⁰⁹¹ is an apocalyptic number.

655091 is a deficient number, since it is larger than the sum of its proper divisors (1909).

655091 is a wasteful number, since it uses less digits than its factorization.

655091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1908.

The product of its (nonzero) digits is 1350, while the sum is 26.

The square root of 655091 is about 809.3769208471. The cubic root of 655091 is about 86.8494776916.

Multiplying 655091 by its sum of digits (26), we get a triangular number (17032366 = T₅₈₃₆).

The spelling of 655091 in words is "six hundred fifty-five thousand, ninety-one".