81667548123 has 16 divisors (see below), whose sum is σ = 131766128640. Its totient is φ = 43922042496.

The previous prime is 81667548119. The next prime is 81667548161. The reversal of 81667548123 is 32184576618.

It is not a de Polignac number, because 81667548123 - 2² = 81667548119 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (81667548113) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 114379963 + ... + 114380676.

It is an arithmetic number, because the mean of its divisors is an integer number (8235383040).

Almost surely, 2^81667548123 is an apocalyptic number.

81667548123 is a deficient number, since it is larger than the sum of its proper divisors (50098580517).

81667548123 is a wasteful number, since it uses less digits than its factorization.

81667548123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228760666.

The product of its digits is 1935360, while the sum is 51.

The spelling of 81667548123 in words is "eighty-one billion, six hundred sixty-seven million, five hundred forty-eight thousand, one hundred twenty-three".