12820145 has 8 divisors (see below), whose sum is σ = 16567656. Its totient is φ = 9467136.

The previous prime is 12820133. The next prime is 12820151. The reversal of 12820145 is 54102821.

It can be written as a sum of positive squares in 4 ways, for example, as 1014049 + 11806096 = 1007^2 + 3436^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 12820145 - 2²⁰ = 11771569 is a prime.

It is a super-2 number, since 2×12820145² = 328712235642050, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12820145.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 98552 + ... + 98681.

It is an arithmetic number, because the mean of its divisors is an integer number (2070957).

Almost surely, 2^12820145 is an apocalyptic number.

It is an amenable number.

12820145 is a deficient number, since it is larger than the sum of its proper divisors (3747511).

12820145 is a wasteful number, since it uses less digits than its factorization.

12820145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197251.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 12820145 is about 3580.5230064894. The cubic root of 12820145 is about 234.0440721040.

Adding to 12820145 its reverse (54102821), we get a palindrome (66922966).

The spelling of 12820145 in words is "twelve million, eight hundred twenty thousand, one hundred forty-five".