655580321 has 4 divisors (see below), whose sum is σ = 715178544. Its totient is φ = 595982100.

The previous prime is 655580297. The next prime is 655580381. The reversal of 655580321 is 123085556.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 655580321 - 2¹⁰ = 655579297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (655580381) 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, 29799095 + ... + 29799116.

It is an arithmetic number, because the mean of its divisors is an integer number (178794636).

Almost surely, 2^655580321 is an apocalyptic number.

It is an amenable number.

655580321 is a deficient number, since it is larger than the sum of its proper divisors (59598223).

655580321 is a wasteful number, since it uses less digits than its factorization.

655580321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59598222.

The product of its (nonzero) digits is 36000, while the sum is 35.

The square root of 655580321 is about 25604.3027829308. The cubic root of 655580321 is about 868.7109641657.

The spelling of 655580321 in words is "six hundred fifty-five million, five hundred eighty thousand, three hundred twenty-one".