2749999981 has 2 divisors, whose sum is σ = 2749999982. Its totient is φ = 2749999980.

The previous prime is 2749999957. The next prime is 2750000051. The reversal of 2749999981 is 1899999472.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2431377481 + 318622500 = 49309^2 + 17850^2 .

It is a cyclic number.

It is not a de Polignac number, because 2749999981 - 2⁵ = 2749999949 is a prime.

It is a super-2 number, since 2×2749999981² = 15124999791000000722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2749999921) 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 as a sum of consecutive naturals, namely, 1374999990 + 1374999991.

It is an arithmetic number, because the mean of its divisors is an integer number (1374999991).

Almost surely, 2^2749999981 is an apocalyptic number.

It is an amenable number.

2749999981 is a deficient number, since it is larger than the sum of its proper divisors (1).

2749999981 is an equidigital number, since it uses as much as digits as its factorization.

2749999981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26453952, while the sum is 67.

The square root of 2749999981 is about 52440.4422273497. The cubic root of 2749999981 is about 1401.0196621011.

The spelling of 2749999981 in words is "two billion, seven hundred forty-nine million, nine hundred ninety-nine thousand, nine hundred eighty-one".