81754492189 has 2 divisors, whose sum is σ = 81754492190. Its totient is φ = 81754492188.

The previous prime is 81754492103. The next prime is 81754492229. The reversal of 81754492189 is 98129445718.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73703019289 + 8051472900 = 271483^2 + 89730^2 .

It is a cyclic number.

It is not a de Polignac number, because 81754492189 - 2²³ = 81746103581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81754496189) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40877246094 + 40877246095.

It is an arithmetic number, because the mean of its divisors is an integer number (40877246095).

Almost surely, 2^81754492189 is an apocalyptic number.

It is an amenable number.

81754492189 is a deficient number, since it is larger than the sum of its proper divisors (1).

81754492189 is an equidigital number, since it uses as much as digits as its factorization.

81754492189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5806080, while the sum is 58.

The spelling of 81754492189 in words is "eighty-one billion, seven hundred fifty-four million, four hundred ninety-two thousand, one hundred eighty-nine".