540911981 has 2 divisors, whose sum is σ = 540911982. Its totient is φ = 540911980.

The previous prime is 540911977. The next prime is 540911989. The reversal of 540911981 is 189119045.

540911981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 276556900 + 264355081 = 16630^2 + 16259^2 .

It is a cyclic number.

It is not a de Polignac number, because 540911981 - 2² = 540911977 is a prime.

It is a super-2 number, since 2×540911981² = 585171542378688722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (540911989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 270455990 + 270455991.

It is an arithmetic number, because the mean of its divisors is an integer number (270455991).

Almost surely, 2^540911981 is an apocalyptic number.

It is an amenable number.

540911981 is a deficient number, since it is larger than the sum of its proper divisors (1).

540911981 is an equidigital number, since it uses as much as digits as its factorization.

540911981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12960, while the sum is 38.

The square root of 540911981 is about 23257.5145060688. The cubic root of 540911981 is about 814.7834525737.

The spelling of 540911981 in words is "five hundred forty million, nine hundred eleven thousand, nine hundred eighty-one".