12721390 has 32 divisors (see below), whose sum is σ = 25233120. Its totient is φ = 4579200.

The previous prime is 12721363. The next prime is 12721391. The reversal of 12721390 is 9312721.

12721390 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12721391) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11460 + ... + 12520.

It is an arithmetic number, because the mean of its divisors is an integer number (788535).

Almost surely, 2^12721390 is an apocalyptic number.

12721390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

12721390 is a deficient number, since it is larger than the sum of its proper divisors (12511730).

12721390 is a wasteful number, since it uses less digits than its factorization.

12721390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1188.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 12721390 is about 3566.7057630256. The cubic root of 12721390 is about 233.4415665676.

It can be divided in two parts, 1272 and 1390, that added together give a palindrome (2662).

The spelling of 12721390 in words is "twelve million, seven hundred twenty-one thousand, three hundred ninety".