55705166561621 has 2 divisors, whose sum is σ = 55705166561622. Its totient is φ = 55705166561620.

The previous prime is 55705166561573. The next prime is 55705166561647. The reversal of 55705166561621 is 12616566150755.

55705166561621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52455399612100 + 3249766949521 = 7242610^2 + 1802711^2 .

It is a cyclic number.

It is not a de Polignac number, because 55705166561621 - 2¹⁰ = 55705166560597 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55705166561221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27852583280810 + 27852583280811.

It is an arithmetic number, because the mean of its divisors is an integer number (27852583280811).

Almost surely, 2^{55705166561621} is an apocalyptic number.

It is an amenable number.

55705166561621 is a deficient number, since it is larger than the sum of its proper divisors (1).

55705166561621 is an equidigital number, since it uses as much as digits as its factorization.

55705166561621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11340000, while the sum is 56.

The spelling of 55705166561621 in words is "fifty-five trillion, seven hundred five billion, one hundred sixty-six million, five hundred sixty-one thousand, six hundred twenty-one".