20727934657 has 2 divisors, whose sum is σ = 20727934658. Its totient is φ = 20727934656.

The previous prime is 20727934637. The next prime is 20727934681. The reversal of 20727934657 is 75643972702.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18044280241 + 2683654416 = 134329^2 + 51804^2 .

It is a cyclic number.

It is not a de Polignac number, because 20727934657 - 2¹⁹ = 20727410369 is a prime.

It is not a weakly prime, because it can be changed into another prime (20727934637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10363967328 + 10363967329.

It is an arithmetic number, because the mean of its divisors is an integer number (10363967329).

Almost surely, 2^20727934657 is an apocalyptic number.

It is an amenable number.

20727934657 is a deficient number, since it is larger than the sum of its proper divisors (1).

20727934657 is an equidigital number, since it uses as much as digits as its factorization.

20727934657 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4445280, while the sum is 52.

The spelling of 20727934657 in words is "twenty billion, seven hundred twenty-seven million, nine hundred thirty-four thousand, six hundred fifty-seven".