12721515 has 8 divisors (see below), whose sum is σ = 20354448. Its totient is φ = 6784800.

The previous prime is 12721477. The next prime is 12721519. The reversal of 12721515 is 51512721.

12721515 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 12721515 - 2¹¹ = 12719467 is a prime.

It is a super-3 number, since 3×12721515³ (a number of 22 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (12721519) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 424036 + ... + 424065.

It is an arithmetic number, because the mean of its divisors is an integer number (2544306).

Almost surely, 2^12721515 is an apocalyptic number.

12721515 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

12721515 is a deficient number, since it is larger than the sum of its proper divisors (7632933).

12721515 is an equidigital number, since it uses as much as digits as its factorization.

12721515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 848109.

The product of its digits is 700, while the sum is 24.

The square root of 12721515 is about 3566.7232861550. The cubic root of 12721515 is about 233.4423311617.

The spelling of 12721515 in words is "twelve million, seven hundred twenty-one thousand, five hundred fifteen".