55666613 has 2 divisors, whose sum is σ = 55666614. Its totient is φ = 55666612.

The previous prime is 55666577. The next prime is 55666621. The reversal of 55666613 is 31666655.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50367409 + 5299204 = 7097^2 + 2302^2 .

It is a cyclic number.

It is not a de Polignac number, because 55666613 - 2¹⁴ = 55650229 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55666813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27833306 + 27833307.

It is an arithmetic number, because the mean of its divisors is an integer number (27833307).

Almost surely, 2^55666613 is an apocalyptic number.

It is an amenable number.

55666613 is a deficient number, since it is larger than the sum of its proper divisors (1).

55666613 is an equidigital number, since it uses as much as digits as its factorization.

55666613 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 97200, while the sum is 38.

The square root of 55666613 is about 7461.0061653908. The cubic root of 55666613 is about 381.8255030256.

The spelling of 55666613 in words is "fifty-five million, six hundred sixty-six thousand, six hundred thirteen".