123255521 has 2 divisors, whose sum is σ = 123255522. Its totient is φ = 123255520.

The previous prime is 123255499. The next prime is 123255523. The reversal of 123255521 is 125552321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63425296 + 59830225 = 7964^2 + 7735^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123255521 is a prime.

Together with 123255523, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (123255523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61627760 + 61627761.

It is an arithmetic number, because the mean of its divisors is an integer number (61627761).

Almost surely, 2^123255521 is an apocalyptic number.

It is an amenable number.

123255521 is a deficient number, since it is larger than the sum of its proper divisors (1).

123255521 is an equidigital number, since it uses as much as digits as its factorization.

123255521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3000, while the sum is 26.

The square root of 123255521 is about 11102.0503061372. The cubic root of 123255521 is about 497.6631230276.

The spelling of 123255521 in words is "one hundred twenty-three million, two hundred fifty-five thousand, five hundred twenty-one".