19917654143 has 2 divisors, whose sum is σ = 19917654144. Its totient is φ = 19917654142.

The previous prime is 19917654139. The next prime is 19917654161. The reversal of 19917654143 is 34145671991.

It is a weak prime.

It is an emirp because it is prime and its reverse (34145671991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19917654143 - 2² = 19917654139 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 19917654091 and 19917654100.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19917657143) 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, 9958827071 + 9958827072.

It is an arithmetic number, because the mean of its divisors is an integer number (9958827072).

Almost surely, 2^19917654143 is an apocalyptic number.

19917654143 is a deficient number, since it is larger than the sum of its proper divisors (1).

19917654143 is an equidigital number, since it uses as much as digits as its factorization.

19917654143 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 816480, while the sum is 50.

The spelling of 19917654143 in words is "nineteen billion, nine hundred seventeen million, six hundred fifty-four thousand, one hundred forty-three".