2015728321 has 4 divisors (see below), whose sum is σ = 2015822592. Its totient is φ = 2015634052.

The previous prime is 2015728307. The next prime is 2015728397. The reversal of 2015728321 is 1238275102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 2015728321 - 2⁷ = 2015728193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2015728721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2040 + ... + 63526.

It is an arithmetic number, because the mean of its divisors is an integer number (503955648).

Almost surely, 2^2015728321 is an apocalyptic number.

It is an amenable number.

2015728321 is a deficient number, since it is larger than the sum of its proper divisors (94271).

2015728321 is an equidigital number, since it uses as much as digits as its factorization.

2015728321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94270.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 2015728321 is about 44896.8631532315. The cubic root of 2015728321 is about 1263.2151702142.

The spelling of 2015728321 in words is "two billion, fifteen million, seven hundred twenty-eight thousand, three hundred twenty-one".