12721842 has 48 divisors (see below), whose sum is σ = 32527872. Its totient is φ = 3516480.

The previous prime is 12721801. The next prime is 12721843. The reversal of 12721842 is 24812721.

It is not an unprimeable number, because it can be changed into a prime (12721843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2278 + ... + 5534.

It is an arithmetic number, because the mean of its divisors is an integer number (677664).

Almost surely, 2^12721842 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12721842, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16263936).

12721842 is an abundant number, since it is smaller than the sum of its proper divisors (19806030).

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

12721842 is a wasteful number, since it uses less digits than its factorization.

12721842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3303 (or 3300 counting only the distinct ones).

The product of its digits is 1792, while the sum is 27.

The square root of 12721842 is about 3566.7691262542. The cubic root of 12721842 is about 233.4443313162. Note that the first 3 decimals are identical.

It can be divided in two parts, 127218 and 42, that added together give a triangular number (127260 = T₅₀₄).

The spelling of 12721842 in words is "twelve million, seven hundred twenty-one thousand, eight hundred forty-two".