12820251 has 4 divisors (see below), whose sum is σ = 17093672. Its totient is φ = 8546832.

The previous prime is 12820243. The next prime is 12820259. The reversal of 12820251 is 15202821.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15202821 = 3 ⋅5067607.

It is an interprime number because it is at equal distance from previous prime (12820243) and next prime (12820259).

It is not a de Polignac number, because 12820251 - 2³ = 12820243 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12820259) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2136706 + ... + 2136711.

It is an arithmetic number, because the mean of its divisors is an integer number (4273418).

Almost surely, 2^12820251 is an apocalyptic number.

12820251 is a deficient number, since it is larger than the sum of its proper divisors (4273421).

12820251 is an equidigital number, since it uses as much as digits as its factorization.

12820251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4273420.

The product of its (nonzero) digits is 320, while the sum is 21.

The square root of 12820251 is about 3580.5378087656. The cubic root of 12820251 is about 234.0447171462.

The spelling of 12820251 in words is "twelve million, eight hundred twenty thousand, two hundred fifty-one".