55549821 has 8 divisors (see below), whose sum is σ = 74599840. Its totient is φ = 36766512.

The previous prime is 55549757. The next prime is 55549841. The reversal of 55549821 is 12894555.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 55549821 - 2⁶ = 55549757 is a prime.

It is a super-2 number, since 2×55549821² = 6171565226264082, 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 55549821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55549841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 66190 + ... + 67023.

It is an arithmetic number, because the mean of its divisors is an integer number (9324980).

Almost surely, 2^55549821 is an apocalyptic number.

It is an amenable number.

55549821 is a deficient number, since it is larger than the sum of its proper divisors (19050019).

55549821 is a wasteful number, since it uses less digits than its factorization.

55549821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133355.

The product of its digits is 72000, while the sum is 39.

The square root of 55549821 is about 7453.1752293905. The cubic root of 55549821 is about 381.5582848779.

The spelling of 55549821 in words is "fifty-five million, five hundred forty-nine thousand, eight hundred twenty-one".