540981081 has 9 divisors (see below), whose sum is σ = 781517919. Its totient is φ = 360607536.

The previous prime is 540981073. The next prime is 540981083. The reversal of 540981081 is 180189045.

The square root of 540981081 is 23259.

It is a perfect power (a square), and thus also a powerful number.

540981081 is a `hidden beast` number, since 540 + 9 + 8 + 108 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 538472025 + 2509056 = 23205^2 + 1584^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 540981081 - 2³ = 540981073 is a prime.

It is a super-2 number, since 2×540981081² = 585321059999857122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (540981083) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 65901 + ... + 73653.

Almost surely, 2^540981081 is an apocalyptic number.

540981081 is the 23259-th square number.

540981081 is the 11630-th centered octagonal number.

It is an amenable number.

540981081 is a deficient number, since it is larger than the sum of its proper divisors (240536838).

540981081 is an frugal number, since it uses more digits than its factorization.

540981081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15512 (or 7756 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 36.

The cubic root of 540981081 is about 814.8181465358.

Multiplying 540981081 by its sum of digits (36), we get a square (19475318916 = 139554²).

The spelling of 540981081 in words is "five hundred forty million, nine hundred eighty-one thousand, eighty-one".