20211565019 has 2 divisors, whose sum is σ = 20211565020. Its totient is φ = 20211565018.

The previous prime is 20211564949. The next prime is 20211565037. The reversal of 20211565019 is 91056511202.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20211565019 is a prime.

It is a super-2 number, since 2×20211565019² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20211565079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105782509 + 10105782510.

It is an arithmetic number, because the mean of its divisors is an integer number (10105782510).

Almost surely, 2^20211565019 is an apocalyptic number.

20211565019 is a deficient number, since it is larger than the sum of its proper divisors (1).

20211565019 is an equidigital number, since it uses as much as digits as its factorization.

20211565019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5400, while the sum is 32.

The spelling of 20211565019 in words is "twenty billion, two hundred eleven million, five hundred sixty-five thousand, nineteen".