27976746781 has 2 divisors, whose sum is σ = 27976746782. Its totient is φ = 27976746780.

The previous prime is 27976746691. The next prime is 27976746797. The reversal of 27976746781 is 18764767972.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23737564900 + 4239181881 = 154070^2 + 65109^2 .

It is a cyclic number.

It is not a de Polignac number, because 27976746781 - 2⁷ = 27976746653 is a prime.

It is a super-2 number, since 2×27976746781² (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 (27976746181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13988373390 + 13988373391.

It is an arithmetic number, because the mean of its divisors is an integer number (13988373391).

Almost surely, 2^27976746781 is an apocalyptic number.

It is an amenable number.

27976746781 is a deficient number, since it is larger than the sum of its proper divisors (1).

27976746781 is an equidigital number, since it uses as much as digits as its factorization.

27976746781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 49787136, while the sum is 64.

The spelling of 27976746781 in words is "twenty-seven billion, nine hundred seventy-six million, seven hundred forty-six thousand, seven hundred eighty-one".