81746478223 has 4 divisors (see below), whose sum is σ = 81755947168. Its totient is φ = 81737009280.

The previous prime is 81746478197. The next prime is 81746478269. The reversal of 81746478223 is 32287464718.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81746478223 - 2²¹ = 81744381071 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81746478823) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4721511 + ... + 4738792.

It is an arithmetic number, because the mean of its divisors is an integer number (20438986792).

Almost surely, 2^81746478223 is an apocalyptic number.

81746478223 is a deficient number, since it is larger than the sum of its proper divisors (9468945).

81746478223 is an equidigital number, since it uses as much as digits as its factorization.

81746478223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9468944.

The product of its digits is 3612672, while the sum is 52.

The spelling of 81746478223 in words is "eighty-one billion, seven hundred forty-six million, four hundred seventy-eight thousand, two hundred twenty-three".