19997343481 has 2 divisors, whose sum is σ = 19997343482. Its totient is φ = 19997343480.

The previous prime is 19997343463. The next prime is 19997343511. The reversal of 19997343481 is 18434379991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18779961600 + 1217381881 = 137040^2 + 34891^2 .

It is a cyclic number.

It is not a de Polignac number, because 19997343481 - 2⁵ = 19997343449 is a prime.

It is a super-2 number, since 2×19997343481² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19997343461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9998671740 + 9998671741.

It is an arithmetic number, because the mean of its divisors is an integer number (9998671741).

Almost surely, 2^19997343481 is an apocalyptic number.

It is an amenable number.

19997343481 is a deficient number, since it is larger than the sum of its proper divisors (1).

19997343481 is an equidigital number, since it uses as much as digits as its factorization.

19997343481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5878656, while the sum is 58.

The spelling of 19997343481 in words is "nineteen billion, nine hundred ninety-seven million, three hundred forty-three thousand, four hundred eighty-one".