55681863728389 has 2 divisors, whose sum is σ = 55681863728390. Its totient is φ = 55681863728388.

The previous prime is 55681863728341. The next prime is 55681863728441. The reversal of 55681863728389 is 98382736818655.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49171369572900 + 6510494155489 = 7012230^2 + 2551567^2 .

It is a cyclic number.

It is not a de Polignac number, because 55681863728389 - 2¹¹ = 55681863726341 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55681863728329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27840931864194 + 27840931864195.

It is an arithmetic number, because the mean of its divisors is an integer number (27840931864195).

Almost surely, 2^{55681863728389} is an apocalyptic number.

It is an amenable number.

55681863728389 is a deficient number, since it is larger than the sum of its proper divisors (1).

55681863728389 is an equidigital number, since it uses as much as digits as its factorization.

55681863728389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4180377600, while the sum is 79.

The spelling of 55681863728389 in words is "fifty-five trillion, six hundred eighty-one billion, eight hundred sixty-three million, seven hundred twenty-eight thousand, three hundred eighty-nine".