55077756581 has 2 divisors, whose sum is σ = 55077756582. Its totient is φ = 55077756580.

The previous prime is 55077756563. The next prime is 55077756593. The reversal of 55077756581 is 18565777055.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46468700356 + 8609056225 = 215566^2 + 92785^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55077756581 is a prime.

It is a super-2 number, since 2×55077756581² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55077756551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27538878290 + 27538878291.

It is an arithmetic number, because the mean of its divisors is an integer number (27538878291).

Almost surely, 2^55077756581 is an apocalyptic number.

It is an amenable number.

55077756581 is a deficient number, since it is larger than the sum of its proper divisors (1).

55077756581 is an equidigital number, since it uses as much as digits as its factorization.

55077756581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10290000, while the sum is 56.

The spelling of 55077756581 in words is "fifty-five billion, seventy-seven million, seven hundred fifty-six thousand, five hundred eighty-one".