655221577 has 4 divisors (see below), whose sum is σ = 655308676. Its totient is φ = 655134480.

The previous prime is 655221559. The next prime is 655221613. The reversal of 655221577 is 775122556.

655221577 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 414692496 + 240529081 = 20364^2 + 15509^2 .

It is a cyclic number.

It is not a de Polignac number, because 655221577 - 2⁷ = 655221449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (655221277) 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, 31074 + ... + 47707.

It is an arithmetic number, because the mean of its divisors is an integer number (163827169).

Almost surely, 2^655221577 is an apocalyptic number.

It is an amenable number.

655221577 is a deficient number, since it is larger than the sum of its proper divisors (87099).

655221577 is an equidigital number, since it uses as much as digits as its factorization.

655221577 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87098.

The product of its digits is 147000, while the sum is 40.

The square root of 655221577 is about 25597.2962830061. The cubic root of 655221577 is about 868.5524777585.

The spelling of 655221577 in words is "six hundred fifty-five million, two hundred twenty-one thousand, five hundred seventy-seven".