12290721 has 8 divisors (see below), whose sum is σ = 16425024. Its totient is φ = 8175120.

The previous prime is 12290713. The next prime is 12290737. The reversal of 12290721 is 12709221.

12290721 is digitally balanced in base 2, because in such base 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 12290721 - 2³ = 12290713 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 12290691 and 12290700.

It is not an unprimeable number, because it can be changed into a prime (12290521) 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, 3061 + ... + 5826.

It is an arithmetic number, because the mean of its divisors is an integer number (2053128).

Almost surely, 2^12290721 is an apocalyptic number.

It is an amenable number.

12290721 is a deficient number, since it is larger than the sum of its proper divisors (4134303).

12290721 is an equidigital number, since it uses as much as digits as its factorization.

12290721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9351.

The product of its (nonzero) digits is 504, while the sum is 24.

The square root of 12290721 is about 3505.8124593309. The cubic root of 12290721 is about 230.7769628093.

Adding to 12290721 its reverse (12709221), we get a palindrome (24999942).

The spelling of 12290721 in words is "twelve million, two hundred ninety thousand, seven hundred twenty-one".