2555123120021 has 2 divisors, whose sum is σ = 2555123120022. Its totient is φ = 2555123120020.

The previous prime is 2555123119999. The next prime is 2555123120071. The reversal of 2555123120021 is 1200213215552.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2209649547121 + 345473572900 = 1486489^2 + 587770^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2555123120021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2555123120071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1277561560010 + 1277561560011.

It is an arithmetic number, because the mean of its divisors is an integer number (1277561560011).

Almost surely, 2^{2555123120021} is an apocalyptic number.

It is an amenable number.

2555123120021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2555123120021 is an equidigital number, since it uses as much as digits as its factorization.

2555123120021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6000, while the sum is 29.

Adding to 2555123120021 its reverse (1200213215552), we get a palindrome (3755336335573).

The spelling of 2555123120021 in words is "two trillion, five hundred fifty-five billion, one hundred twenty-three million, one hundred twenty thousand, twenty-one".