1165261957729 has 3 divisors (see below), whose sum is σ = 1165263037203. Its totient is φ = 1165260878256.

The previous prime is 1165261957711. The next prime is 1165261957747. The reversal of 1165261957729 is 9277591625611.

The square root of 1165261957729 is 1079473.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is an interprime number because it is at equal distance from previous prime (1165261957711) and next prime (1165261957747).

It can be written as a sum of positive squares in only one way, i.e., 656253909025 + 509008048704 = 810095^2 + 713448^2 .

It is not a de Polignac number, because 1165261957729 - 2⁹ = 1165261957217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1165261957709) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 539737 + ... + 1619209.

It is an arithmetic number, because the mean of its divisors is an integer number (388421012401).

Almost surely, 2^{1165261957729} is an apocalyptic number.

1165261957729 is the 1079473-rd square number.

1165261957729 is the 539737-th centered octagonal number.

It is an amenable number.

1165261957729 is a deficient number, since it is larger than the sum of its proper divisors (1079474).

1165261957729 is an frugal number, since it uses more digits than its factorization.

1165261957729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2158946 (or 1079473 counting only the distinct ones).

The product of its digits is 14288400, while the sum is 61.

The spelling of 1165261957729 in words is "one trillion, one hundred sixty-five billion, two hundred sixty-one million, nine hundred fifty-seven thousand, seven hundred twenty-nine".