27648701581 has 2 divisors, whose sum is σ = 27648701582. Its totient is φ = 27648701580.

The previous prime is 27648701527. The next prime is 27648701629. The reversal of 27648701581 is 18510784672.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26570630025 + 1078071556 = 163005^2 + 32834^2 .

It is a cyclic number.

It is not a de Polignac number, because 27648701581 - 2¹⁵ = 27648668813 is a prime.

It is a super-2 number, since 2×27648701581² (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 (27648771581) 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, 13824350790 + 13824350791.

It is an arithmetic number, because the mean of its divisors is an integer number (13824350791).

Almost surely, 2^27648701581 is an apocalyptic number.

It is an amenable number.

27648701581 is a deficient number, since it is larger than the sum of its proper divisors (1).

27648701581 is an equidigital number, since it uses as much as digits as its factorization.

27648701581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 752640, while the sum is 49.

The spelling of 27648701581 in words is "twenty-seven billion, six hundred forty-eight million, seven hundred one thousand, five hundred eighty-one".