55185409 has 2 divisors, whose sum is σ = 55185410. Its totient is φ = 55185408.

The previous prime is 55185401. The next prime is 55185479. The reversal of 55185409 is 90458155.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39025009 + 16160400 = 6247^2 + 4020^2 .

It is a cyclic number.

It is not a de Polignac number, because 55185409 - 2³ = 55185401 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (55185401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27592704 + 27592705.

It is an arithmetic number, because the mean of its divisors is an integer number (27592705).

Almost surely, 2^55185409 is an apocalyptic number.

It is an amenable number.

55185409 is a deficient number, since it is larger than the sum of its proper divisors (1).

55185409 is an equidigital number, since it uses as much as digits as its factorization.

55185409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36000, while the sum is 37.

The square root of 55185409 is about 7428.6882422134. The cubic root of 55185409 is about 380.7221010925.

The spelling of 55185409 in words is "fifty-five million, one hundred eighty-five thousand, four hundred nine".