55481609 has 2 divisors, whose sum is σ = 55481610. Its totient is φ = 55481608.

The previous prime is 55481603. The next prime is 55481617. The reversal of 55481609 is 90618455.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 32947600 + 22534009 = 5740^2 + 4747^2 .

It is a cyclic number.

It is not a de Polignac number, because 55481609 - 2⁴ = 55481593 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (55481603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27740804 + 27740805.

It is an arithmetic number, because the mean of its divisors is an integer number (27740805).

Almost surely, 2^55481609 is an apocalyptic number.

It is an amenable number.

55481609 is a deficient number, since it is larger than the sum of its proper divisors (1).

55481609 is an equidigital number, since it uses as much as digits as its factorization.

55481609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43200, while the sum is 38.

The square root of 55481609 is about 7448.5977875034. The cubic root of 55481609 is about 381.4020436653.

The spelling of 55481609 in words is "fifty-five million, four hundred eighty-one thousand, six hundred nine".