55573821 has 6 divisors (see below), whose sum is σ = 80273310. Its totient is φ = 37049208.

The previous prime is 55573801. The next prime is 55573823. The reversal of 55573821 is 12837555.

55573821 is a `hidden beast` number, since 5 + 5 + 573 + 82 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 42068196 + 13505625 = 6486^2 + 3675^2 .

It is not a de Polignac number, because 55573821 - 2⁵ = 55573789 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55573823) 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 5 ways as a sum of consecutive naturals, for example, 3087426 + ... + 3087443.

It is an arithmetic number, because the mean of its divisors is an integer number (13378885).

Almost surely, 2^55573821 is an apocalyptic number.

It is an amenable number.

55573821 is a deficient number, since it is larger than the sum of its proper divisors (24699489).

55573821 is a wasteful number, since it uses less digits than its factorization.

55573821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6174875 (or 6174872 counting only the distinct ones).

The product of its digits is 42000, while the sum is 36.

The square root of 55573821 is about 7454.7851075668. The cubic root of 55573821 is about 381.6132270312.

The spelling of 55573821 in words is "fifty-five million, five hundred seventy-three thousand, eight hundred twenty-one".