12721809701 has 2 divisors, whose sum is σ = 12721809702. Its totient is φ = 12721809700.

The previous prime is 12721809671. The next prime is 12721809739. The reversal of 12721809701 is 10790812721.

It is an a-pointer prime, because the next prime (12721809739) can be obtained adding 12721809701 to its sum of digits (38).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7665177601 + 5056632100 = 87551^2 + 71110^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12721809701 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12721809761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6360904850 + 6360904851.

It is an arithmetic number, because the mean of its divisors is an integer number (6360904851).

Almost surely, 2^12721809701 is an apocalyptic number.

It is an amenable number.

12721809701 is a deficient number, since it is larger than the sum of its proper divisors (1).

12721809701 is an equidigital number, since it uses as much as digits as its factorization.

12721809701 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14112, while the sum is 38.

The spelling of 12721809701 in words is "twelve billion, seven hundred twenty-one million, eight hundred nine thousand, seven hundred one".