40009509 has 6 divisors (see below), whose sum is σ = 57791526. Its totient is φ = 26673000.

The previous prime is 40009477. The next prime is 40009511. The reversal of 40009509 is 90590004.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 38750625 + 1258884 = 6225^2 + 1122^2 .

It is not a de Polignac number, because 40009509 - 2⁵ = 40009477 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40009559) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2222742 + ... + 2222759.

It is an arithmetic number, because the mean of its divisors is an integer number (9631921).

Almost surely, 2^40009509 is an apocalyptic number.

It is an amenable number.

40009509 is a deficient number, since it is larger than the sum of its proper divisors (17782017).

40009509 is a wasteful number, since it uses less digits than its factorization.

40009509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4445507 (or 4445504 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 27.

The square root of 40009509 is about 6325.3070281212. The cubic root of 40009509 is about 342.0222874569.

The spelling of 40009509 in words is "forty million, nine thousand, five hundred nine".