81373423 has 2 divisors, whose sum is σ = 81373424. Its totient is φ = 81373422.

The previous prime is 81373421. The next prime is 81373429. The reversal of 81373423 is 32437318.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81373423 - 2¹ = 81373421 is a prime.

Together with 81373421, 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 (81373421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40686711 + 40686712.

It is an arithmetic number, because the mean of its divisors is an integer number (40686712).

Almost surely, 2^81373423 is an apocalyptic number.

81373423 is a deficient number, since it is larger than the sum of its proper divisors (1).

81373423 is an equidigital number, since it uses as much as digits as its factorization.

81373423 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12096, while the sum is 31.

The square root of 81373423 is about 9020.7218669018. The cubic root of 81373423 is about 433.3387521347.

It can be divided in two parts, 81373 and 423, that added together give a square (81796 = 286²).

The spelling of 81373423 in words is "eighty-one million, three hundred seventy-three thousand, four hundred twenty-three".