55516609 has 2 divisors, whose sum is σ = 55516610. Its totient is φ = 55516608.

The previous prime is 55516607. The next prime is 55516619. The reversal of 55516609 is 90661555.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49660209 + 5856400 = 7047^2 + 2420^2 .

It is a cyclic number.

It is not a de Polignac number, because 55516609 - 2¹ = 55516607 is a prime.

Together with 55516607, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (55516607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27758304 + 27758305.

It is an arithmetic number, because the mean of its divisors is an integer number (27758305).

Almost surely, 2^55516609 is an apocalyptic number.

It is an amenable number.

55516609 is a deficient number, since it is larger than the sum of its proper divisors (1).

55516609 is an equidigital number, since it uses as much as digits as its factorization.

55516609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40500, while the sum is 37.

The square root of 55516609 is about 7450.9468525819. The cubic root of 55516609 is about 381.4822279865.

The spelling of 55516609 in words is "fifty-five million, five hundred sixteen thousand, six hundred nine".