81358423 has 2 divisors, whose sum is σ = 81358424. Its totient is φ = 81358422.

The previous prime is 81358421. The next prime is 81358441. The reversal of 81358423 is 32485318.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81358423 - 2¹ = 81358421 is a prime.

Together with 81358421, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81358421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40679211 + 40679212.

It is an arithmetic number, because the mean of its divisors is an integer number (40679212).

Almost surely, 2^81358423 is an apocalyptic number.

81358423 is a deficient number, since it is larger than the sum of its proper divisors (1).

81358423 is an equidigital number, since it uses as much as digits as its factorization.

81358423 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23040, while the sum is 34.

The square root of 81358423 is about 9019.8904095338. The cubic root of 81358423 is about 433.3121239455.

The spelling of 81358423 in words is "eighty-one million, three hundred fifty-eight thousand, four hundred twenty-three".