54565781 has 4 divisors (see below), whose sum is σ = 55460364. Its totient is φ = 53671200.

The previous prime is 54565769. The next prime is 54565783. The reversal of 54565781 is 18756545.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18756545 = 5 ⋅3751309.

It can be written as a sum of positive squares in 2 ways, for example, as 2235025 + 52330756 = 1495^2 + 7234^2 .

It is a cyclic number.

It is not a de Polignac number, because 54565781 - 2¹⁸ = 54303637 is a prime.

It is a super-3 number, since 3×54565781³ (a number of 24 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (54565783) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 447200 + ... + 447321.

It is an arithmetic number, because the mean of its divisors is an integer number (13865091).

Almost surely, 2^54565781 is an apocalyptic number.

It is an amenable number.

54565781 is a deficient number, since it is larger than the sum of its proper divisors (894583).

54565781 is an equidigital number, since it uses as much as digits as its factorization.

54565781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 894582.

The product of its digits is 168000, while the sum is 41.

The square root of 54565781 is about 7386.8654380596. The cubic root of 54565781 is about 379.2918042433.

The spelling of 54565781 in words is "fifty-four million, five hundred sixty-five thousand, seven hundred eighty-one".