2491751729 has 4 divisors (see below), whose sum is σ = 2532600180. Its totient is φ = 2450903280.

The previous prime is 2491751711. The next prime is 2491751737. The reversal of 2491751729 is 9271571942.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 223801600 + 2267950129 = 14960^2 + 47623^2 .

It is a cyclic number.

It is not a de Polignac number, because 2491751729 - 2¹² = 2491747633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2491751929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20424134 + ... + 20424255.

It is an arithmetic number, because the mean of its divisors is an integer number (633150045).

Almost surely, 2^2491751729 is an apocalyptic number.

It is an amenable number.

2491751729 is a deficient number, since it is larger than the sum of its proper divisors (40848451).

2491751729 is an equidigital number, since it uses as much as digits as its factorization.

2491751729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40848450.

The product of its digits is 317520, while the sum is 47.

The square root of 2491751729 is about 49917.4491435610. The cubic root of 2491751729 is about 1355.7145469403.

The spelling of 2491751729 in words is "two billion, four hundred ninety-one million, seven hundred fifty-one thousand, seven hundred twenty-nine".