540123561 has 6 divisors (see below), whose sum is σ = 780178490. Its totient is φ = 360082368.

The previous prime is 540123547. The next prime is 540123581. The reversal of 540123561 is 165321045.

It can be written as a sum of positive squares in only one way, i.e., 472801536 + 67322025 = 21744^2 + 8205^2 .

It is not a de Polignac number, because 540123561 - 2⁷ = 540123433 is a prime.

It is a super-2 number, since 2×540123561² = 583466922294641442, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (540123581) 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 5 ways as a sum of consecutive naturals, for example, 30006856 + ... + 30006873.

Almost surely, 2^540123561 is an apocalyptic number.

It is an amenable number.

540123561 is a deficient number, since it is larger than the sum of its proper divisors (240054929).

540123561 is a wasteful number, since it uses less digits than its factorization.

540123561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60013735 (or 60013732 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 540123561 is about 23240.5585345964. The cubic root of 540123561 is about 814.3873906409.

The spelling of 540123561 in words is "five hundred forty million, one hundred twenty-three thousand, five hundred sixty-one".