19481781166873 has 2 divisors, whose sum is σ = 19481781166874. Its totient is φ = 19481781166872.

The previous prime is 19481781166843. The next prime is 19481781166877. The reversal of 19481781166873 is 37866118718491.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16441054329049 + 3040726837824 = 4054757^2 + 1743768^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19481781166873 is a prime.

It is a super-3 number, since 3×19481781166873³ (a number of 41 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (19481781166877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9740890583436 + 9740890583437.

It is an arithmetic number, because the mean of its divisors is an integer number (9740890583437).

Almost surely, 2^{19481781166873} is an apocalyptic number.

It is an amenable number.

19481781166873 is a deficient number, since it is larger than the sum of its proper divisors (1).

19481781166873 is an equidigital number, since it uses as much as digits as its factorization.

19481781166873 is an evil number, because the sum of its binary digits is even.

The product of its digits is 97542144, while the sum is 70.

The spelling of 19481781166873 in words is "nineteen trillion, four hundred eighty-one billion, seven hundred eighty-one million, one hundred sixty-six thousand, eight hundred seventy-three".