55081993 has 2 divisors, whose sum is σ = 55081994. Its totient is φ = 55081992.

The previous prime is 55081981. The next prime is 55081997. The reversal of 55081993 is 39918055.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39778249 + 15303744 = 6307^2 + 3912^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55081993 is a prime.

It is not a weakly prime, because it can be changed into another prime (55081997) 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 as a sum of consecutive naturals, namely, 27540996 + 27540997.

It is an arithmetic number, because the mean of its divisors is an integer number (27540997).

Almost surely, 2^55081993 is an apocalyptic number.

It is an amenable number.

55081993 is a deficient number, since it is larger than the sum of its proper divisors (1).

55081993 is an equidigital number, since it uses as much as digits as its factorization.

55081993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48600, while the sum is 40.

The square root of 55081993 is about 7421.7243953141. The cubic root of 55081993 is about 380.4841313244.

The spelling of 55081993 in words is "fifty-five million, eighty-one thousand, nine hundred ninety-three".