7215728520 has 768 divisors, whose sum is σ = 30201937920. Its totient is φ = 1341204480.

The previous prime is 7215728483. The next prime is 7215728543. The reversal of 7215728520 is 258275127.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 56816697 + ... + 56816823.

It is an arithmetic number, because the mean of its divisors is an integer number (39325440).

Almost surely, 2^7215728520 is an apocalyptic number.

7215728520 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7215728520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15100968960).

7215728520 is an abundant number, since it is smaller than the sum of its proper divisors (22986209400).

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

7215728520 is a wasteful number, since it uses less digits than its factorization.

7215728520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226 (or 211 counting only the distinct ones).

The product of its (nonzero) digits is 78400, while the sum is 39.

The square root of 7215728520 is about 84945.4443746102. Note that the first 3 decimals coincide. The cubic root of 7215728520 is about 1932.3838316814.

The spelling of 7215728520 in words is "seven billion, two hundred fifteen million, seven hundred twenty-eight thousand, five hundred twenty".