55516661 has 2 divisors, whose sum is σ = 55516662. Its totient is φ = 55516660.

The previous prime is 55516639. The next prime is 55516667. The reversal of 55516661 is 16661555.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55502500 + 14161 = 7450^2 + 119^2 .

It is a cyclic number.

It is not a de Polignac number, because 55516661 - 2⁶ = 55516597 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55516667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27758330 + 27758331.

It is an arithmetic number, because the mean of its divisors is an integer number (27758331).

Almost surely, 2^55516661 is an apocalyptic number.

It is an amenable number.

55516661 is a deficient number, since it is larger than the sum of its proper divisors (1).

55516661 is an equidigital number, since it uses as much as digits as its factorization.

55516661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27000, while the sum is 35.

The square root of 55516661 is about 7450.9503420705. The cubic root of 55516661 is about 381.4823470925.

The spelling of 55516661 in words is "fifty-five million, five hundred sixteen thousand, six hundred sixty-one".