655120557 has 72 divisors (see below), whose sum is σ = 1203431424. Its totient is φ = 336016512.

The previous prime is 655120553. The next prime is 655120603. The reversal of 655120557 is 755021556.

It is a happy number.

It is not a de Polignac number, because 655120557 - 2² = 655120553 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (655120553) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 393108 + ... + 394770.

Almost surely, 2^655120557 is an apocalyptic number.

It is an amenable number.

655120557 is a deficient number, since it is larger than the sum of its proper divisors (548310867).

655120557 is a wasteful number, since it uses less digits than its factorization.

655120557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1739 (or 1723 counting only the distinct ones).

The product of its (nonzero) digits is 52500, while the sum is 36.

The square root of 655120557 is about 25595.3229516644. The cubic root of 655120557 is about 868.5078385687.

Subtracting 655120557 from its reverse (755021556), we obtain a palindrome (99900999).

The spelling of 655120557 in words is "six hundred fifty-five million, one hundred twenty thousand, five hundred fifty-seven".