2109857749487 has 2 divisors, whose sum is σ = 2109857749488. Its totient is φ = 2109857749486.

The previous prime is 2109857749459. The next prime is 2109857749541. The reversal of 2109857749487 is 7849477589012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2109857749487 - 2¹⁴ = 2109857733103 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2109857749487.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2109857749187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1054928874743 + 1054928874744.

It is an arithmetic number, because the mean of its divisors is an integer number (1054928874744).

Almost surely, 2^{2109857749487} is an apocalyptic number.

2109857749487 is a deficient number, since it is larger than the sum of its proper divisors (1).

2109857749487 is an equidigital number, since it uses as much as digits as its factorization.

2109857749487 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 284497920, while the sum is 71.

The spelling of 2109857749487 in words is "two trillion, one hundred nine billion, eight hundred fifty-seven million, seven hundred forty-nine thousand, four hundred eighty-seven".