27380728321 has 2 divisors, whose sum is σ = 27380728322. Its totient is φ = 27380728320.

The previous prime is 27380728267. The next prime is 27380728351. The reversal of 27380728321 is 12382708372.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27378666225 + 2062096 = 165465^2 + 1436^2 .

It is a cyclic number.

It is not a de Polignac number, because 27380728321 - 2¹⁵ = 27380695553 is a prime.

It is a super-2 number, since 2×27380728321² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (27380728351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13690364160 + 13690364161.

It is an arithmetic number, because the mean of its divisors is an integer number (13690364161).

Almost surely, 2^27380728321 is an apocalyptic number.

It is an amenable number.

27380728321 is a deficient number, since it is larger than the sum of its proper divisors (1).

27380728321 is an equidigital number, since it uses as much as digits as its factorization.

27380728321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 225792, while the sum is 43.

The spelling of 27380728321 in words is "twenty-seven billion, three hundred eighty million, seven hundred twenty-eight thousand, three hundred twenty-one".