82171726728 has 128 divisors (see below), whose sum is σ = 267708913920. Its totient is φ = 20396851200.

The previous prime is 82171726657. The next prime is 82171726787. The reversal of 82171726728 is 82762717128.

It is a super-2 number, since 2×82171726728² (a number of 23 digits) contains 22 as substring.

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

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1069473 + ... + 1143728.

It is an arithmetic number, because the mean of its divisors is an integer number (2091475890).

Almost surely, 2^82171726728 is an apocalyptic number.

It is an amenable number.

82171726728 is an abundant number, since it is smaller than the sum of its proper divisors (185537187192).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

82171726728 is a wasteful number, since it uses less digits than its factorization.

82171726728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2213247 (or 2213243 counting only the distinct ones).

The product of its digits is 1053696, while the sum is 51.

The spelling of 82171726728 in words is "eighty-two billion, one hundred seventy-one million, seven hundred twenty-six thousand, seven hundred twenty-eight".