3123121909 has 2 divisors, whose sum is σ = 3123121910. Its totient is φ = 3123121908.

The previous prime is 3123121889. The next prime is 3123121921. The reversal of 3123121909 is 9091213213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3026650225 + 96471684 = 55015^2 + 9822^2 .

It is an emirp because it is prime and its reverse (9091213213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3123121909 - 2¹³ = 3123113717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3123181909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1561560954 + 1561560955.

It is an arithmetic number, because the mean of its divisors is an integer number (1561560955).

Almost surely, 2^3123121909 is an apocalyptic number.

It is an amenable number.

3123121909 is a deficient number, since it is larger than the sum of its proper divisors (1).

3123121909 is an equidigital number, since it uses as much as digits as its factorization.

3123121909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2916, while the sum is 31.

The square root of 3123121909 is about 55884.8987562830. The cubic root of 3123121909 is about 1461.7159266056.

The spelling of 3123121909 in words is "three billion, one hundred twenty-three million, one hundred twenty-one thousand, nine hundred nine".