20516521219 has 2 divisors, whose sum is σ = 20516521220. Its totient is φ = 20516521218.

The previous prime is 20516521217. The next prime is 20516521241. The reversal of 20516521219 is 91212561502.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20516521219 - 2¹ = 20516521217 is a prime.

It is a super-2 number, since 2×20516521219² (a number of 21 digits) contains 22 as substring.

Together with 20516521217, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20516521217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10258260609 + 10258260610.

It is an arithmetic number, because the mean of its divisors is an integer number (10258260610).

Almost surely, 2^20516521219 is an apocalyptic number.

20516521219 is a deficient number, since it is larger than the sum of its proper divisors (1).

20516521219 is an equidigital number, since it uses as much as digits as its factorization.

20516521219 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10800, while the sum is 34.

The spelling of 20516521219 in words is "twenty billion, five hundred sixteen million, five hundred twenty-one thousand, two hundred nineteen".