2491179252409 has 3 divisors (see below), whose sum is σ = 2491180830757. Its totient is φ = 2491177674062.

The previous prime is 2491179252383. The next prime is 2491179252449. The reversal of 2491179252409 is 9042529711942.

The square root of 2491179252409 is 1578347.

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 not a de Polignac number, because 2491179252409 - 2¹⁷ = 2491179121337 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 2491179252409.

It is not an unprimeable number, because it can be changed into a prime (2491179252449) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 789174 + ... + 2367520.

Almost surely, 2^{2491179252409} is an apocalyptic number.

2491179252409 is the 1578347-th square number.

2491179252409 is the 789174-th centered octagonal number.

It is an amenable number.

2491179252409 is a deficient number, since it is larger than the sum of its proper divisors (1578348).

2491179252409 is an frugal number, since it uses more digits than its factorization.

2491179252409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3156694 (or 1578347 counting only the distinct ones).

The product of its (nonzero) digits is 3265920, while the sum is 55.

The spelling of 2491179252409 in words is "two trillion, four hundred ninety-one billion, one hundred seventy-nine million, two hundred fifty-two thousand, four hundred nine".