55665559 has 2 divisors, whose sum is σ = 55665560. Its totient is φ = 55665558.

The previous prime is 55665557. The next prime is 55665563. The reversal of 55665559 is 95556655.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 55665559 - 2¹ = 55665557 is a prime.

Together with 55665557, 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 (55665551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27832779 + 27832780.

It is an arithmetic number, because the mean of its divisors is an integer number (27832780).

Almost surely, 2^55665559 is an apocalyptic number.

55665559 is a deficient number, since it is larger than the sum of its proper divisors (1).

55665559 is an equidigital number, since it uses as much as digits as its factorization.

55665559 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1012500, while the sum is 46.

The square root of 55665559 is about 7460.9355311516. The cubic root of 55665559 is about 381.8230931633.

The spelling of 55665559 in words is "fifty-five million, six hundred sixty-five thousand, five hundred fifty-nine".