55666649 has 2 divisors, whose sum is σ = 55666650. Its totient is φ = 55666648.

The previous prime is 55666621. The next prime is 55666657. The reversal of 55666649 is 94666655.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47169424 + 8497225 = 6868^2 + 2915^2 .

It is a cyclic number.

It is not a de Polignac number, because 55666649 - 2⁸ = 55666393 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (55666679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27833324 + 27833325.

It is an arithmetic number, because the mean of its divisors is an integer number (27833325).

Almost surely, 2^55666649 is an apocalyptic number.

It is an amenable number.

55666649 is a deficient number, since it is larger than the sum of its proper divisors (1).

55666649 is an equidigital number, since it uses as much as digits as its factorization.

55666649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1166400, while the sum is 47.

The square root of 55666649 is about 7461.0085779337. The cubic root of 55666649 is about 381.8255853354.

The spelling of 55666649 in words is "fifty-five million, six hundred sixty-six thousand, six hundred forty-nine".