2115491707729 has 9 divisors (see below), whose sum is σ = 2120163575337. Its totient is φ = 2110830121764.

The previous prime is 2115491707727. The next prime is 2115491707733. The reversal of 2115491707729 is 9277071945112.

The square root of 2115491707729 is 1454473.

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

It is not a de Polignac number, because 2115491707729 - 2¹ = 2115491707727 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2115491707729.

It is not an unprimeable number, because it can be changed into a prime (2115491707723) 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, 795595402 + ... + 795598060.

It is an arithmetic number, because the mean of its divisors is an integer number (235573730593).

Almost surely, 2^{2115491707729} is an apocalyptic number.

2115491707729 is the 1454473-rd square number.

2115491707729 is the 727237-th centered octagonal number.

It is an amenable number.

2115491707729 is a deficient number, since it is larger than the sum of its proper divisors (4671867608).

2115491707729 is an frugal number, since it uses more digits than its factorization.

2115491707729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6412 (or 3206 counting only the distinct ones).

The product of its (nonzero) digits is 2222640, while the sum is 55.

The spelling of 2115491707729 in words is "two trillion, one hundred fifteen billion, four hundred ninety-one million, seven hundred seven thousand, seven hundred twenty-nine".