72170028 has 72 divisors (see below), whose sum is σ = 216233472. Its totient is φ = 20618064.

The previous prime is 72169987. The next prime is 72170029. The reversal of 72170028 is 82007127.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 72169983 and 72170010.

It is not an unprimeable number, because it can be changed into a prime (72170029) 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, 1501 + ... + 12107.

Almost surely, 2^72170028 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72170028, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108116736).

72170028 is an abundant number, since it is smaller than the sum of its proper divisors (144063444).

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

72170028 is a wasteful number, since it uses less digits than its factorization.

72170028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10633 (or 10619 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 27.

The square root of 72170028 is about 8495.2944622303. The cubic root of 72170028 is about 416.3439817009.

The spelling of 72170028 in words is "seventy-two million, one hundred seventy thousand, twenty-eight".