40000649 has 4 divisors (see below), whose sum is σ = 43077636. Its totient is φ = 36923664.

The previous prime is 40000627. The next prime is 40000651. The reversal of 40000649 is 94600004.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 24255625 + 15745024 = 4925^2 + 3968^2 .

It is a cyclic number.

It is not a de Polignac number, because 40000649 - 2¹² = 39996553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40000669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1538474 + ... + 1538499.

It is an arithmetic number, because the mean of its divisors is an integer number (10769409).

Almost surely, 2^40000649 is an apocalyptic number.

It is an amenable number.

40000649 is a deficient number, since it is larger than the sum of its proper divisors (3076987).

40000649 is a wasteful number, since it uses less digits than its factorization.

40000649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3076986.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 40000649 is about 6324.6066280837. The cubic root of 40000649 is about 341.9970389493.

The spelling of 40000649 in words is "forty million, six hundred forty-nine", and thus it is an aban number.