2109505657837 has 2 divisors, whose sum is σ = 2109505657838. Its totient is φ = 2109505657836.

The previous prime is 2109505657801. The next prime is 2109505657871. The reversal of 2109505657837 is 7387565059012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1373351953801 + 736153704036 = 1171901^2 + 857994^2 .

It is a cyclic number.

It is not a de Polignac number, because 2109505657837 - 2⁷ = 2109505657709 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2109505655837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1054752828918 + 1054752828919.

It is an arithmetic number, because the mean of its divisors is an integer number (1054752828919).

Almost surely, 2^{2109505657837} is an apocalyptic number.

It is an amenable number.

2109505657837 is a deficient number, since it is larger than the sum of its proper divisors (1).

2109505657837 is an equidigital number, since it uses as much as digits as its factorization.

2109505657837 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15876000, while the sum is 58.

The spelling of 2109505657837 in words is "two trillion, one hundred nine billion, five hundred five million, six hundred fifty-seven thousand, eight hundred thirty-seven".