40687309 has 8 divisors (see below), whose sum is σ = 45001880. Its totient is φ = 36542016.

The previous prime is 40687301. The next prime is 40687321. The reversal of 40687309 is 90378604.

It can be written as a sum of positive squares in 4 ways, for example, as 13616100 + 27071209 = 3690^2 + 5203^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 40687309 - 2³ = 40687301 is a prime.

It is a super-2 number, since 2×40687309² = 3310914227322962, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40687301) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41814 + ... + 42775.

It is an arithmetic number, because the mean of its divisors is an integer number (5625235).

Almost surely, 2^40687309 is an apocalyptic number.

It is an amenable number.

40687309 is a deficient number, since it is larger than the sum of its proper divisors (4314571).

40687309 is a wasteful number, since it uses less digits than its factorization.

40687309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84639.

The product of its (nonzero) digits is 36288, while the sum is 37.

The square root of 40687309 is about 6378.6604393086. The cubic root of 40687309 is about 343.9428791266.

The spelling of 40687309 in words is "forty million, six hundred eighty-seven thousand, three hundred nine".