55081909 has 2 divisors, whose sum is σ = 55081910. Its totient is φ = 55081908.

The previous prime is 55081907. The next prime is 55081913. The reversal of 55081909 is 90918055.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 37859409 + 17222500 = 6153^2 + 4150^2 .

It is a cyclic number.

It is not a de Polignac number, because 55081909 - 2¹ = 55081907 is a prime.

Together with 55081907, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55081903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27540954 + 27540955.

It is an arithmetic number, because the mean of its divisors is an integer number (27540955).

Almost surely, 2^55081909 is an apocalyptic number.

It is an amenable number.

55081909 is a deficient number, since it is larger than the sum of its proper divisors (1).

55081909 is an equidigital number, since it uses as much as digits as its factorization.

55081909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16200, while the sum is 37.

The square root of 55081909 is about 7421.7187362497. The cubic root of 55081909 is about 380.4839379117.

The spelling of 55081909 in words is "fifty-five million, eighty-one thousand, nine hundred nine".