2551121311729 has 9 divisors (see below), whose sum is σ = 2557113738699. Its totient is φ = 2545142906040.

The previous prime is 2551121311709. The next prime is 2551121311747. The reversal of 2551121311729 is 9271131211552.

The square root of 2551121311729 is 1597223.

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

It can be written as a sum of positive squares in only one way, i.e., 2538588957025 + 12532354704 = 1593295^2 + 111948^2 .

It is not a de Polignac number, because 2551121311729 - 2³³ = 2542531377137 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2551121311691 and 2551121311700.

It is not an unprimeable number, because it can be changed into a prime (2551121311709) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 784234867 + ... + 784238119.

Almost surely, 2^{2551121311729} is an apocalyptic number.

2551121311729 is the 1597223-rd square number.

2551121311729 is the 798612-nd centered octagonal number.

It is an amenable number.

2551121311729 is a deficient number, since it is larger than the sum of its proper divisors (5992426970).

2551121311729 is an frugal number, since it uses more digits than its factorization.

2551121311729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7488 (or 3744 counting only the distinct ones).

The product of its digits is 37800, while the sum is 40.

The spelling of 2551121311729 in words is "two trillion, five hundred fifty-one billion, one hundred twenty-one million, three hundred eleven thousand, seven hundred twenty-nine".