13631604821 has 2 divisors, whose sum is σ = 13631604822. Its totient is φ = 13631604820.

The previous prime is 13631604799. The next prime is 13631604829. The reversal of 13631604821 is 12840613631.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12398822500 + 1232782321 = 111350^2 + 35111^2 .

It is an emirp because it is prime and its reverse (12840613631) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13631604821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13631604829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6815802410 + 6815802411.

It is an arithmetic number, because the mean of its divisors is an integer number (6815802411).

Almost surely, 2^13631604821 is an apocalyptic number.

It is an amenable number.

13631604821 is a deficient number, since it is larger than the sum of its proper divisors (1).

13631604821 is an equidigital number, since it uses as much as digits as its factorization.

13631604821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 35.

The spelling of 13631604821 in words is "thirteen billion, six hundred thirty-one million, six hundred four thousand, eight hundred twenty-one".