81866146323 has 24 divisors (see below), whose sum is σ = 119243353392. Its totient is φ = 49933298688.

The previous prime is 81866146321. The next prime is 81866146333. The reversal of 81866146323 is 32364166818.

It is not a de Polignac number, because 81866146323 - 2¹ = 81866146321 is a prime.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (81866146321) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 657186 + ... + 771767.

It is an arithmetic number, because the mean of its divisors is an integer number (4968473058).

Almost surely, 2^81866146323 is an apocalyptic number.

81866146323 is a deficient number, since it is larger than the sum of its proper divisors (37377207069).

81866146323 is a wasteful number, since it uses less digits than its factorization.

81866146323 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1429095 (or 1429082 counting only the distinct ones).

The product of its digits is 995328, while the sum is 48.

The spelling of 81866146323 in words is "eighty-one billion, eight hundred sixty-six million, one hundred forty-six thousand, three hundred twenty-three".