2561795514721 has 9 divisors (see below), whose sum is σ = 2647151110449. Its totient is φ = 2479108932900.

The previous prime is 2561795514673. The next prime is 2561795514731. The reversal of 2561795514721 is 1274155971652.

The square root of 2561795514721 is 1600561.

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

It is not a de Polignac number, because 2561795514721 - 2¹¹ = 2561795512673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2561795514731) 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, 49591576 + ... + 49643206.

It is an arithmetic number, because the mean of its divisors is an integer number (294127901161).

Almost surely, 2^{2561795514721} is an apocalyptic number.

2561795514721 is the 1600561-st square number.

2561795514721 is the 800281-st centered octagonal number.

It is an amenable number.

2561795514721 is a deficient number, since it is larger than the sum of its proper divisors (85355595728).

2561795514721 is an frugal number, since it uses more digits than its factorization.

2561795514721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103324 (or 51662 counting only the distinct ones).

The product of its digits is 5292000, while the sum is 55.

It can be divided in two parts, 2561795 and 514721, that added together give a square (3076516 = 1754²).

The spelling of 2561795514721 in words is "two trillion, five hundred sixty-one billion, seven hundred ninety-five million, five hundred fourteen thousand, seven hundred twenty-one".