19429543681 has 2 divisors, whose sum is σ = 19429543682. Its totient is φ = 19429543680.

The previous prime is 19429543603. The next prime is 19429543699. The reversal of 19429543681 is 18634592491.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19288765456 + 140778225 = 138884^2 + 11865^2 .

It is a cyclic number.

It is not a de Polignac number, because 19429543681 - 2²¹ = 19427446529 is a prime.

It is a super-2 number, since 2×19429543681² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19429543481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9714771840 + 9714771841.

It is an arithmetic number, because the mean of its divisors is an integer number (9714771841).

Almost surely, 2^19429543681 is an apocalyptic number.

It is an amenable number.

19429543681 is a deficient number, since it is larger than the sum of its proper divisors (1).

19429543681 is an equidigital number, since it uses as much as digits as its factorization.

19429543681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1866240, while the sum is 52.

The spelling of 19429543681 in words is "nineteen billion, four hundred twenty-nine million, five hundred forty-three thousand, six hundred eighty-one".