55321657 has 4 divisors (see below), whose sum is σ = 55389220. Its totient is φ = 55254096.

The previous prime is 55321649. The next prime is 55321661. The reversal of 55321657 is 75612355.

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 46730896 + 8590761 = 6836^2 + 2931^2 .

It is a cyclic number.

It is not a de Polignac number, because 55321657 - 2³ = 55321649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55321627) 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 3 ways as a sum of consecutive naturals, for example, 32538 + ... + 34195.

It is an arithmetic number, because the mean of its divisors is an integer number (13847305).

Almost surely, 2^55321657 is an apocalyptic number.

It is an amenable number.

55321657 is a deficient number, since it is larger than the sum of its proper divisors (67563).

55321657 is an equidigital number, since it uses as much as digits as its factorization.

55321657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67562.

The product of its digits is 31500, while the sum is 34.

The square root of 55321657 is about 7437.8529832204. The cubic root of 55321657 is about 381.0351668984.

The spelling of 55321657 in words is "fifty-five million, three hundred twenty-one thousand, six hundred fifty-seven".