20516055251 has 2 divisors, whose sum is σ = 20516055252. Its totient is φ = 20516055250.

The previous prime is 20516055247. The next prime is 20516055253. The reversal of 20516055251 is 15255061502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20516055251 - 2² = 20516055247 is a prime.

Together with 20516055253, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20516055253) 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, 10258027625 + 10258027626.

It is an arithmetic number, because the mean of its divisors is an integer number (10258027626).

Almost surely, 2^20516055251 is an apocalyptic number.

20516055251 is a deficient number, since it is larger than the sum of its proper divisors (1).

20516055251 is an equidigital number, since it uses as much as digits as its factorization.

20516055251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15000, while the sum is 32.

The spelling of 20516055251 in words is "twenty billion, five hundred sixteen million, fifty-five thousand, two hundred fifty-one".