13136558064721 has 27 divisors (see below), whose sum is σ = 16547624399601. Its totient is φ = 10393499267424.

The previous prime is 13136558064691. The next prime is 13136558064733. The reversal of 13136558064721 is 12746085563131.

The square root of 13136558064721 is 3624439.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 269013382225 + 12867544682496 = 518665^2 + 3587136^2 .

It is not a de Polignac number, because 13136558064721 - 2⁵ = 13136558064689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13136558064121) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 329804035 + ... + 329843863.

It is an arithmetic number, because the mean of its divisors is an integer number (612874977763).

Almost surely, 2^{13136558064721} is an apocalyptic number.

13136558064721 is the 3624439-th square number.

13136558064721 is the 1812220-th centered octagonal number.

It is an amenable number.

13136558064721 is a deficient number, since it is larger than the sum of its proper divisors (3411066334880).

13136558064721 is an frugal number, since it uses more digits than its factorization.

13136558064721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79698 (or 39849 counting only the distinct ones).

The product of its (nonzero) digits is 3628800, while the sum is 52.

The spelling of 13136558064721 in words is "thirteen trillion, one hundred thirty-six billion, five hundred fifty-eight million, sixty-four thousand, seven hundred twenty-one".