123121013 has 2 divisors, whose sum is σ = 123121014. Its totient is φ = 123121012.

The previous prime is 123121003. The next prime is 123121049. The reversal of 123121013 is 310121321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 70442449 + 52678564 = 8393^2 + 7258^2 .

It is an emirp because it is prime and its reverse (310121321) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123121013 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123121003) 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 as a sum of consecutive naturals, namely, 61560506 + 61560507.

It is an arithmetic number, because the mean of its divisors is an integer number (61560507).

Almost surely, 2^123121013 is an apocalyptic number.

It is an amenable number.

123121013 is a deficient number, since it is larger than the sum of its proper divisors (1).

123121013 is an equidigital number, since it uses as much as digits as its factorization.

123121013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 123121013 is about 11095.9908525557. The cubic root of 123121013 is about 497.4820248886.

Adding to 123121013 its reverse (310121321), we get a palindrome (433242334).

The spelling of 123121013 in words is "one hundred twenty-three million, one hundred twenty-one thousand, thirteen".