12820209194 has 24 divisors (see below), whose sum is σ = 20834275500. Its totient is φ = 5913917568.

The previous prime is 12820209139. The next prime is 12820209197. The reversal of 12820209194 is 49190202821.

It can be written as a sum of positive squares in 6 ways, for example, as 329241025 + 12490968169 = 18145^2 + 111763^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12820209197) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 713432 + ... + 731180.

Almost surely, 2^12820209194 is an apocalyptic number.

12820209194 is a deficient number, since it is larger than the sum of its proper divisors (8014066306).

12820209194 is a wasteful number, since it uses less digits than its factorization.

12820209194 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19914 (or 19901 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 38.

The spelling of 12820209194 in words is "twelve billion, eight hundred twenty million, two hundred nine thousand, one hundred ninety-four".