655040123 has 4 divisors (see below), whose sum is σ = 657851688. Its totient is φ = 652228560.

The previous prime is 655040083. The next prime is 655040131. The reversal of 655040123 is 321040556.

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 655040123 - 2⁶ = 655040059 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 655040092 and 655040101.

It is not an unprimeable number, because it can be changed into a prime (655045123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1405433 + ... + 1405898.

It is an arithmetic number, because the mean of its divisors is an integer number (164462922).

Almost surely, 2^655040123 is an apocalyptic number.

655040123 is a deficient number, since it is larger than the sum of its proper divisors (2811565).

655040123 is a wasteful number, since it uses less digits than its factorization.

655040123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2811564.

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 655040123 is about 25593.7516398046. The cubic root of 655040123 is about 868.4722927353.

Adding to 655040123 its reverse (321040556), we get a palindrome (976080679).

The spelling of 655040123 in words is "six hundred fifty-five million, forty thousand, one hundred twenty-three".