12816202821 has 4 divisors (see below), whose sum is σ = 17088270432. Its totient is φ = 8544135212.

The previous prime is 12816202769. The next prime is 12816202859. The reversal of 12816202821 is 12820261821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12820261821 = 3 ⋅4273420607.

It is a cyclic number.

It is not a de Polignac number, because 12816202821 - 2²³ = 12807814213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12816202871) 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, 2136033801 + ... + 2136033806.

It is an arithmetic number, because the mean of its divisors is an integer number (4272067608).

Almost surely, 2^12816202821 is an apocalyptic number.

It is an amenable number.

12816202821 is a deficient number, since it is larger than the sum of its proper divisors (4272067611).

12816202821 is an equidigital number, since it uses as much as digits as its factorization.

12816202821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4272067610.

The product of its (nonzero) digits is 6144, while the sum is 33.

The spelling of 12816202821 in words is "twelve billion, eight hundred sixteen million, two hundred two thousand, eight hundred twenty-one".