21198927719 has 2 divisors, whose sum is σ = 21198927720. Its totient is φ = 21198927718.

The previous prime is 21198927689. The next prime is 21198927721. The reversal of 21198927719 is 91772989112.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21198927719 is a prime.

It is a super-2 number, since 2×21198927719² (a number of 21 digits) contains 22 as substring.

Together with 21198927721, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21198927119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10599463859 + 10599463860.

It is an arithmetic number, because the mean of its divisors is an integer number (10599463860).

Almost surely, 2^21198927719 is an apocalyptic number.

21198927719 is a deficient number, since it is larger than the sum of its proper divisors (1).

21198927719 is an equidigital number, since it uses as much as digits as its factorization.

21198927719 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1143072, while the sum is 56.

The spelling of 21198927719 in words is "twenty-one billion, one hundred ninety-eight million, nine hundred twenty-seven thousand, seven hundred nineteen".