40013 has 2 divisors, whose sum is σ = 40014. Its totient is φ = 40012.

The previous prime is 40009. The next prime is 40031. The reversal of 40013 is 31004.

40013 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with next prime (40031) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 33124 + 6889 = 182^2 + 83^2 .

It is a cyclic number.

It is not a de Polignac number, because 40013 - 2² = 40009 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20006 + 20007.

It is an arithmetic number, because the mean of its divisors is an integer number (20007).

2⁴⁰⁰¹³ is an apocalyptic number.

It is an amenable number.

40013 is a deficient number, since it is larger than the sum of its proper divisors (1).

40013 is an equidigital number, since it uses as much as digits as its factorization.

40013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12, while the sum is 8.

The square root of 40013 is about 200.0324973598. The cubic root of 40013 is about 34.2032234801.

Adding to 40013 its reverse (31004), we get a palindrome (71017).

Subtracting from 40013 its reverse (31004), we obtain a palindrome (9009).

It can be divided in two parts, 4001 and 3, that added together give a palindrome (4004).

The spelling of 40013 in words is "forty thousand, thirteen".