40392509 has 2 divisors, whose sum is σ = 40392510. Its totient is φ = 40392508.

The previous prime is 40392481. The next prime is 40392511. The reversal of 40392509 is 90529304.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40005625 + 386884 = 6325^2 + 622^2 .

It is a cyclic number.

It is not a de Polignac number, because 40392509 - 2¹⁶ = 40326973 is a prime.

Together with 40392511, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40392529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20196254 + 20196255.

It is an arithmetic number, because the mean of its divisors is an integer number (20196255).

Almost surely, 2^40392509 is an apocalyptic number.

It is an amenable number.

40392509 is a deficient number, since it is larger than the sum of its proper divisors (1).

40392509 is an equidigital number, since it uses as much as digits as its factorization.

40392509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9720, while the sum is 32.

The square root of 40392509 is about 6355.5101290140. The cubic root of 40392509 is about 343.1101851151.

The spelling of 40392509 in words is "forty million, three hundred ninety-two thousand, five hundred nine".