40006809 has 6 divisors (see below), whose sum is σ = 57787626. Its totient is φ = 26671200.

The previous prime is 40006793. The next prime is 40006819. The reversal of 40006809 is 90860004.

It can be written as a sum of positive squares in only one way, i.e., 38192400 + 1814409 = 6180^2 + 1347^2 .

It is not a de Polignac number, because 40006809 - 2⁴ = 40006793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (40006819) 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, 2222592 + ... + 2222609.

It is an arithmetic number, because the mean of its divisors is an integer number (9631271).

Almost surely, 2^40006809 is an apocalyptic number.

It is an amenable number.

40006809 is a deficient number, since it is larger than the sum of its proper divisors (17780817).

40006809 is a wasteful number, since it uses less digits than its factorization.

40006809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4445207 (or 4445204 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 40006809 is about 6325.0935961454. The cubic root of 40006809 is about 342.0145936114.

The spelling of 40006809 in words is "forty million, six thousand, eight hundred nine".