36721 has 2 divisors, whose sum is σ = 36722.
Its totient is φ = 36720.
The previous prime is 36713. The next prime is 36739. The reversal of 36721 is 12763.
36721 = 1352 + 1362.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 18496 + 18225 = 136^2 + 135^2
It is an emirp because it is prime and its reverse (12763) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 36721 - 23 = 36713 is a prime.
It is a Chen prime.
It is an alternating number because its digits alternate between odd and even.
36721 is a lucky number.
It is a nialpdrome in base 9.
It is not a weakly prime, because it can be changed into another prime (36761) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18360 + 18361.
It is an arithmetic number, because the mean of its divisors is an integer number (18361).
236721 is an apocalyptic number.
36721 is the 136-th centered square number.
It is an amenable number.
36721 is a deficient number, since it is larger than the sum of its proper divisors (1).
36721 is an equidigital number, since it uses as much as digits as its factorization.
36721 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 252, while the sum is 19.
The square root of 36721 is about 191.6272423222.
The cubic root of 36721 is about 33.2382512621.
It can be divided in two parts, 36 and 721, that added together give a palindrome (757).
The spelling of 36721 in words is "thirty-six thousand, seven hundred twenty-one".