13646252821 has 2 divisors, whose sum is σ = 13646252822. Its totient is φ = 13646252820.

The previous prime is 13646252813. The next prime is 13646252833. The reversal of 13646252821 is 12825264631.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12833717796 + 812535025 = 113286^2 + 28505^2 .

It is a cyclic number.

It is not a de Polignac number, because 13646252821 - 2³ = 13646252813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13646252861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6823126410 + 6823126411.

It is an arithmetic number, because the mean of its divisors is an integer number (6823126411).

Almost surely, 2^13646252821 is an apocalyptic number.

It is an amenable number.

13646252821 is a deficient number, since it is larger than the sum of its proper divisors (1).

13646252821 is an equidigital number, since it uses as much as digits as its factorization.

13646252821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 138240, while the sum is 40.

The spelling of 13646252821 in words is "thirteen billion, six hundred forty-six million, two hundred fifty-two thousand, eight hundred twenty-one".