655613391 has 8 divisors (see below), whose sum is σ = 875013120. Its totient is φ = 436644632.

The previous prime is 655613359. The next prime is 655613393. The reversal of 655613391 is 193316556.

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 655613391 - 2⁵ = 655613359 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (655613393) 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, 104175 + ... + 110288.

It is an arithmetic number, because the mean of its divisors is an integer number (109376640).

Almost surely, 2^655613391 is an apocalyptic number.

655613391 is a deficient number, since it is larger than the sum of its proper divisors (219399729).

655613391 is a wasteful number, since it uses less digits than its factorization.

655613391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215485.

The product of its digits is 72900, while the sum is 39.

The square root of 655613391 is about 25604.9485646818. The cubic root of 655613391 is about 868.7255709639.

The spelling of 655613391 in words is "six hundred fifty-five million, six hundred thirteen thousand, three hundred ninety-one".