2691287318437 has 2 divisors, whose sum is σ = 2691287318438. Its totient is φ = 2691287318436.

The previous prime is 2691287318347. The next prime is 2691287318443. The reversal of 2691287318437 is 7348137821962.

Together with previous prime (2691287318347) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1708560080161 + 982727238276 = 1307119^2 + 991326^2 .

It is a cyclic number.

It is not a de Polignac number, because 2691287318437 - 2¹⁹ = 2691286794149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2691287312437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1345643659218 + 1345643659219.

It is an arithmetic number, because the mean of its divisors is an integer number (1345643659219).

Almost surely, 2^{2691287318437} is an apocalyptic number.

It is an amenable number.

2691287318437 is a deficient number, since it is larger than the sum of its proper divisors (1).

2691287318437 is an equidigital number, since it uses as much as digits as its factorization.

2691287318437 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24385536, while the sum is 61.

The spelling of 2691287318437 in words is "two trillion, six hundred ninety-one billion, two hundred eighty-seven million, three hundred eighteen thousand, four hundred thirty-seven".