2543642649109 has 2 divisors, whose sum is σ = 2543642649110. Its totient is φ = 2543642649108.

The previous prime is 2543642649059. The next prime is 2543642649193. The reversal of 2543642649109 is 9019462463452.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2279354121009 + 264288528100 = 1509753^2 + 514090^2 .

It is a cyclic number.

It is not a de Polignac number, because 2543642649109 - 2¹¹ = 2543642647061 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2543642649109.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2543642643109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1271821324554 + 1271821324555.

It is an arithmetic number, because the mean of its divisors is an integer number (1271821324555).

Almost surely, 2^{2543642649109} is an apocalyptic number.

It is an amenable number.

2543642649109 is a deficient number, since it is larger than the sum of its proper divisors (1).

2543642649109 is an equidigital number, since it uses as much as digits as its factorization.

2543642649109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11197440, while the sum is 55.

The spelling of 2543642649109 in words is "two trillion, five hundred forty-three billion, six hundred forty-two million, six hundred forty-nine thousand, one hundred nine".