7213728 has 48 divisors (see below), whose sum is σ = 19093536. Its totient is φ = 2384640.

The previous prime is 7213709. The next prime is 7213747. The reversal of 7213728 is 8273127.

It is an interprime number because it is at equal distance from previous prime (7213709) and next prime (7213747).

It is a tau number, because it is divible by the number of its divisors (48).

It is a junction number, because it is equal to n+sod(n) for n = 7213695 and 7213704.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15418 + ... + 15878.

It is an arithmetic number, because the mean of its divisors is an integer number (397782).

Almost surely, 2^7213728 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 7213728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9546768).

7213728 is an abundant number, since it is smaller than the sum of its proper divisors (11879808).

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

7213728 is a wasteful number, since it uses less digits than its factorization.

7213728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 637 (or 629 counting only the distinct ones).

The product of its digits is 4704, while the sum is 30.

The square root of 7213728 is about 2685.8384165843. The cubic root of 7213728 is about 193.2205234339.

The spelling of 7213728 in words is "seven million, two hundred thirteen thousand, seven hundred twenty-eight".