13631621 has 2 divisors, whose sum is σ = 13631622. Its totient is φ = 13631620.

The previous prime is 13631593. The next prime is 13631641. The reversal of 13631621 is 12613631.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7230721 + 6400900 = 2689^2 + 2530^2 .

It is an emirp because it is prime and its reverse (12613631) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13631621 - 2¹⁰ = 13630597 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13631641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6815810 + 6815811.

It is an arithmetic number, because the mean of its divisors is an integer number (6815811).

Almost surely, 2^13631621 is an apocalyptic number.

It is an amenable number.

13631621 is a deficient number, since it is larger than the sum of its proper divisors (1).

13631621 is an equidigital number, since it uses as much as digits as its factorization.

13631621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 648, while the sum is 23.

The square root of 13631621 is about 3692.1025175366. The cubic root of 13631621 is about 238.8814909393.

The spelling of 13631621 in words is "thirteen million, six hundred thirty-one thousand, six hundred twenty-one".