82172538 has 48 divisors (see below), whose sum is σ = 204774336. Its totient is φ = 23328000.

The previous prime is 82172533. The next prime is 82172581. The reversal of 82172538 is 83527128.

It is a super-2 number, since 2×82172538² = 13504652002722888, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (82172533) 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, 18538 + ... + 22538.

It is an arithmetic number, because the mean of its divisors is an integer number (4266132).

Almost surely, 2^82172538 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 82172538, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102387168).

82172538 is an abundant number, since it is smaller than the sum of its proper divisors (122601798).

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

82172538 is a wasteful number, since it uses less digits than its factorization.

82172538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4179 (or 4176 counting only the distinct ones).

The product of its digits is 26880, while the sum is 36.

The square root of 82172538 is about 9064.9069493294. The cubic root of 82172538 is about 434.7526457389.

The spelling of 82172538 in words is "eighty-two million, one hundred seventy-two thousand, five hundred thirty-eight".