81726123 has 8 divisors (see below), whose sum is σ = 115378128. Its totient is φ = 51279104.

The previous prime is 81726121. The next prime is 81726149. The reversal of 81726123 is 32162718.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81726123 - 2¹ = 81726121 is a prime.

It is a super-2 number, since 2×81726123² = 13358318361222258, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81726121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 801186 + ... + 801287.

It is an arithmetic number, because the mean of its divisors is an integer number (14422266).

Almost surely, 2^81726123 is an apocalyptic number.

81726123 is a deficient number, since it is larger than the sum of its proper divisors (33652005).

81726123 is a wasteful number, since it uses less digits than its factorization.

81726123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1602493.

The product of its digits is 4032, while the sum is 30.

The square root of 81726123 is about 9040.2501624679. The cubic root of 81726123 is about 433.9639287767.

The spelling of 81726123 in words is "eighty-one million, seven hundred twenty-six thousand, one hundred twenty-three".