2539138325561 has 2 divisors, whose sum is σ = 2539138325562. Its totient is φ = 2539138325560.

The previous prime is 2539138325497. The next prime is 2539138325599. The reversal of 2539138325561 is 1655238319352.

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., 1372133447161 + 1167004878400 = 1171381^2 + 1080280^2 .

It is a cyclic number.

It is not a de Polignac number, because 2539138325561 - 2⁶ = 2539138325497 is a prime.

It is not a weakly prime, because it can be changed into another prime (2539138325761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1269569162780 + 1269569162781.

It is an arithmetic number, because the mean of its divisors is an integer number (1269569162781).

Almost surely, 2^{2539138325561} is an apocalyptic number.

It is an amenable number.

2539138325561 is a deficient number, since it is larger than the sum of its proper divisors (1).

2539138325561 is an equidigital number, since it uses as much as digits as its factorization.

2539138325561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5832000, while the sum is 53.

The spelling of 2539138325561 in words is "two trillion, five hundred thirty-nine billion, one hundred thirty-eight million, three hundred twenty-five thousand, five hundred sixty-one".