81790127 has 2 divisors, whose sum is σ = 81790128. Its totient is φ = 81790126.

The previous prime is 81790073. The next prime is 81790129. The reversal of 81790127 is 72109718.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81790127 - 2¹⁴ = 81773743 is a prime.

It is a super-2 number, since 2×81790127² = 13379249749352258, which contains 22 as substring.

Together with 81790129, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81790129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40895063 + 40895064.

It is an arithmetic number, because the mean of its divisors is an integer number (40895064).

Almost surely, 2^81790127 is an apocalyptic number.

81790127 is a deficient number, since it is larger than the sum of its proper divisors (1).

81790127 is an equidigital number, since it uses as much as digits as its factorization.

81790127 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7056, while the sum is 35.

The square root of 81790127 is about 9043.7894159473. The cubic root of 81790127 is about 434.0771858302.

The spelling of 81790127 in words is "eighty-one million, seven hundred ninety thousand, one hundred twenty-seven".