7147728 has 90 divisors (see below), whose sum is σ = 23292594. Its totient is φ = 2040192.

The previous prime is 7147709. The next prime is 7147747. The reversal of 7147728 is 8277417.

It is an interprime number because it is at equal distance from previous prime (7147709) and next prime (7147747).

It can be written as a sum of positive squares in only one way, i.e., 3732624 + 3415104 = 1932^2 + 1848^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

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

It is a junction number, because it is equal to n+sod(n) for n = 7147692 and 7147701.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 6550 + ... + 7562.

Almost surely, 2^7147728 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 7147728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11646297).

7147728 is an abundant number, since it is smaller than the sum of its proper divisors (16144866).

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

7147728 is a wasteful number, since it uses less digits than its factorization.

7147728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1041 (or 1025 counting only the distinct ones).

The product of its digits is 21952, while the sum is 36.

The square root of 7147728 is about 2673.5235177570. The cubic root of 7147728 is about 192.6294446172.

It can be divided in two parts, 7147 and 728, that added together give a triangular number (7875 = T₁₂₅).

The spelling of 7147728 in words is "seven million, one hundred forty-seven thousand, seven hundred twenty-eight".