81516554323 has 2 divisors, whose sum is σ = 81516554324. Its totient is φ = 81516554322.

The previous prime is 81516554279. The next prime is 81516554333. The reversal of 81516554323 is 32345561518.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81516554323 is a prime.

It is a super-4 number, since 4×81516554323⁴ (a number of 45 digits) contains 4444 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81516554323.

It is not a weakly prime, because it can be changed into another prime (81516554333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40758277161 + 40758277162.

It is an arithmetic number, because the mean of its divisors is an integer number (40758277162).

Almost surely, 2^81516554323 is an apocalyptic number.

81516554323 is a deficient number, since it is larger than the sum of its proper divisors (1).

81516554323 is an equidigital number, since it uses as much as digits as its factorization.

81516554323 is an evil number, because the sum of its binary digits is even.

The product of its digits is 432000, while the sum is 43.

The spelling of 81516554323 in words is "eighty-one billion, five hundred sixteen million, five hundred fifty-four thousand, three hundred twenty-three".