55774428581 has 2 divisors, whose sum is σ = 55774428582. Its totient is φ = 55774428580.

The previous prime is 55774428571. The next prime is 55774428613. The reversal of 55774428581 is 18582447755.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 50270124100 + 5504304481 = 224210^2 + 74191^2 .

It is a cyclic number.

It is not a de Polignac number, because 55774428581 - 2⁶ = 55774428517 is a prime.

It is a super-2 number, since 2×55774428581² (a number of 22 digits) contains 22 as substring.

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 (55774428511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27887214290 + 27887214291.

It is an arithmetic number, because the mean of its divisors is an integer number (27887214291).

Almost surely, 2^55774428581 is an apocalyptic number.

It is an amenable number.

55774428581 is a deficient number, since it is larger than the sum of its proper divisors (1).

55774428581 is an equidigital number, since it uses as much as digits as its factorization.

55774428581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12544000, while the sum is 56.

The spelling of 55774428581 in words is "fifty-five billion, seven hundred seventy-four million, four hundred twenty-eight thousand, five hundred eighty-one".