55547281 has 4 divisors (see below), whose sum is σ = 55570212. Its totient is φ = 55524352.

The previous prime is 55547263. The next prime is 55547287. The reversal of 55547281 is 18274555.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 46036225 + 9511056 = 6785^2 + 3084^2 .

It is a cyclic number.

It is not a de Polignac number, because 55547281 - 2⁷ = 55547153 is a prime.

It is a super-2 number, since 2×55547281² = 6171000852985922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 55547281.

It is not an unprimeable number, because it can be changed into a prime (55547287) 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, 7336 + ... + 12841.

It is an arithmetic number, because the mean of its divisors is an integer number (13892553).

Almost surely, 2^55547281 is an apocalyptic number.

It is an amenable number.

55547281 is a deficient number, since it is larger than the sum of its proper divisors (22931).

55547281 is a wasteful number, since it uses less digits than its factorization.

55547281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22930.

The product of its digits is 56000, while the sum is 37.

The square root of 55547281 is about 7453.0048302681. The cubic root of 55547281 is about 381.5524692407.

The spelling of 55547281 in words is "fifty-five million, five hundred forty-seven thousand, two hundred eighty-one".