27731830661 has 2 divisors, whose sum is σ = 27731830662. Its totient is φ = 27731830660.

The previous prime is 27731830639. The next prime is 27731830663. The reversal of 27731830661 is 16603813772.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19510781761 + 8221048900 = 139681^2 + 90670^2 .

It is a cyclic number.

It is not a de Polignac number, because 27731830661 - 2¹⁰ = 27731829637 is a prime.

Together with 27731830663, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27731830663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13865915330 + 13865915331.

It is an arithmetic number, because the mean of its divisors is an integer number (13865915331).

Almost surely, 2^27731830661 is an apocalyptic number.

It is an amenable number.

27731830661 is a deficient number, since it is larger than the sum of its proper divisors (1).

27731830661 is an equidigital number, since it uses as much as digits as its factorization.

27731830661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 254016, while the sum is 44.

The spelling of 27731830661 in words is "twenty-seven billion, seven hundred thirty-one million, eight hundred thirty thousand, six hundred sixty-one".