655195591 has 4 divisors (see below), whose sum is σ = 657806184. Its totient is φ = 652585000.

The previous prime is 655195559. The next prime is 655195627. The reversal of 655195591 is 195591556.

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 655195591 - 2⁵ = 655195559 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (655195501) 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, 1304920 + ... + 1305421.

It is an arithmetic number, because the mean of its divisors is an integer number (164451546).

Almost surely, 2^655195591 is an apocalyptic number.

655195591 is a deficient number, since it is larger than the sum of its proper divisors (2610593).

655195591 is a wasteful number, since it uses less digits than its factorization.

655195591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2610592.

The product of its digits is 303750, while the sum is 46.

The square root of 655195591 is about 25596.7886853019. The cubic root of 655195591 is about 868.5409953817.

The spelling of 655195591 in words is "six hundred fifty-five million, one hundred ninety-five thousand, five hundred ninety-one".