2511312491 has 4 divisors (see below), whose sum is σ = 2541569352. Its totient is φ = 2481055632.

The previous prime is 2511312481. The next prime is 2511312499. The reversal of 2511312491 is 1942131152.

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

It is a cyclic number.

It is not a de Polignac number, because 2511312491 - 2²⁶ = 2444203627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2511312499) 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 3 ways as a sum of consecutive naturals, for example, 15128306 + ... + 15128471.

It is an arithmetic number, because the mean of its divisors is an integer number (635392338).

Almost surely, 2^2511312491 is an apocalyptic number.

2511312491 is a deficient number, since it is larger than the sum of its proper divisors (30256861).

2511312491 is an equidigital number, since it uses as much as digits as its factorization.

2511312491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30256860.

The product of its digits is 2160, while the sum is 29.

The square root of 2511312491 is about 50112.9972262686. The cubic root of 2511312491 is about 1359.2528499542.

The spelling of 2511312491 in words is "two billion, five hundred eleven million, three hundred twelve thousand, four hundred ninety-one".