2718187981 has 4 divisors (see below), whose sum is σ = 2728001212. Its totient is φ = 2708374752.

The previous prime is 2718187963. The next prime is 2718188059. The reversal of 2718187981 is 1897818172.

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 1405575081 + 1312612900 = 37491^2 + 36230^2 .

It is a cyclic number.

It is not a de Polignac number, because 2718187981 - 2¹¹ = 2718185933 is a prime.

It is a super-2 number, since 2×2718187981² = 14777091800105712722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2718187931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4906200 + ... + 4906753.

It is an arithmetic number, because the mean of its divisors is an integer number (682000303).

Almost surely, 2^2718187981 is an apocalyptic number.

It is an amenable number.

2718187981 is a deficient number, since it is larger than the sum of its proper divisors (9813231).

2718187981 is an equidigital number, since it uses as much as digits as its factorization.

2718187981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9813230.

The product of its digits is 451584, while the sum is 52.

The square root of 2718187981 is about 52136.2444082809. The cubic root of 2718187981 is about 1395.5963639372.

The spelling of 2718187981 in words is "two billion, seven hundred eighteen million, one hundred eighty-seven thousand, nine hundred eighty-one".