40129 has 2 divisors, whose sum is σ = 40130. Its totient is φ = 40128.

The previous prime is 40127. The next prime is 40151. The reversal of 40129 is 92104.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21904 + 18225 = 148^2 + 135^2 .

It is a cyclic number.

It is not a de Polignac number, because 40129 - 2¹ = 40127 is a prime.

It is a super-2 number, since 2×40129² = 3220673282, which contains 22 as substring.

Together with 40127, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (40123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20064 + 20065.

It is an arithmetic number, because the mean of its divisors is an integer number (20065).

2⁴⁰¹²⁹ is an apocalyptic number.

It is an amenable number.

40129 is a deficient number, since it is larger than the sum of its proper divisors (1).

40129 is an equidigital number, since it uses as much as digits as its factorization.

40129 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 40129 is about 200.3222404028. The cubic root of 40129 is about 34.2362439652.

It can be divided in two parts, 40 and 129, that added together give a square (169 = 13²).

The spelling of 40129 in words is "forty thousand, one hundred twenty-nine".