81774004519 has 2 divisors, whose sum is σ = 81774004520. Its totient is φ = 81774004518.

The previous prime is 81774004493. The next prime is 81774004583. The reversal of 81774004519 is 91540047718.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81774004519 - 2²⁷ = 81639786791 is a prime.

It is a super-2 number, since 2×81774004519² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81774004919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40887002259 + 40887002260.

It is an arithmetic number, because the mean of its divisors is an integer number (40887002260).

Almost surely, 2^81774004519 is an apocalyptic number.

81774004519 is a deficient number, since it is larger than the sum of its proper divisors (1).

81774004519 is an equidigital number, since it uses as much as digits as its factorization.

81774004519 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 282240, while the sum is 46.

The spelling of 81774004519 in words is "eighty-one billion, seven hundred seventy-four million, four thousand, five hundred nineteen".