81814123 has 2 divisors, whose sum is σ = 81814124. Its totient is φ = 81814122.

The previous prime is 81814111. The next prime is 81814127. The reversal of 81814123 is 32141818.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81814123 - 2²¹ = 79716971 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 81814091 and 81814100.

It is not a weakly prime, because it can be changed into another prime (81814127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40907061 + 40907062.

It is an arithmetic number, because the mean of its divisors is an integer number (40907062).

Almost surely, 2^81814123 is an apocalyptic number.

81814123 is a deficient number, since it is larger than the sum of its proper divisors (1).

81814123 is an equidigital number, since it uses as much as digits as its factorization.

81814123 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1536, while the sum is 28.

The square root of 81814123 is about 9045.1159749337. The cubic root of 81814123 is about 434.1196322641.

It can be divided in two parts, 818 and 14123, that added together give a palindrome (14941).

The spelling of 81814123 in words is "eighty-one million, eight hundred fourteen thousand, one hundred twenty-three".