15641 has 2 divisors, whose sum is σ = 15642. Its totient is φ = 15640.
The previous prime is 15629. The next prime is 15643. The reversal of 15641 is 14651.
It is a happy number.
15641 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 15625 + 16 = 125^2 + 4^2 .
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-15641 is a prime.
Together with 15643, it forms a pair of twin primes.
It is a Chen prime.
It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 15641.
It is not a weakly prime, because it can be changed into another prime (15643) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7820 + 7821.
It is an arithmetic number, because the mean of its divisors is an integer number (7821).
15641 is a Friedman number, since it can be written as 5^6+(1+1)^4, using all its digits and the basic arithmetic operations.
215641 is an apocalyptic number.
It is an amenable number.
15641 is a deficient number, since it is larger than the sum of its proper divisors (1).
15641 is an equidigital number, since it uses as much as digits as its factorization.
15641 is an evil number, because the sum of its binary digits is even.
The product of its digits is 120, while the sum is 17.
The square root of 15641 is about 125.0639836244. The cubic root of 15641 is about 25.0085304223.
Subtracting from 15641 its reverse (14651), we obtain a triangular number (990 = T44).
It can be divided in two parts, 15 and 641, that added together give a palindrome (656).
The spelling of 15641 in words is "fifteen thousand, six hundred forty-one".
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