40209749 has 4 divisors (see below), whose sum is σ = 40229280. Its totient is φ = 40190220.

The previous prime is 40209733. The next prime is 40209751. The reversal of 40209749 is 94790204.

40209749 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 40209749 - 2⁴ = 40209733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40209649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6257 + ... + 10934.

It is an arithmetic number, because the mean of its divisors is an integer number (10057320).

Almost surely, 2^40209749 is an apocalyptic number.

It is an amenable number.

40209749 is a deficient number, since it is larger than the sum of its proper divisors (19531).

40209749 is a wasteful number, since it uses less digits than its factorization.

40209749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19530.

The product of its (nonzero) digits is 18144, while the sum is 35.

The square root of 40209749 is about 6341.1157535563. The cubic root of 40209749 is about 342.5919237519.

The spelling of 40209749 in words is "forty million, two hundred nine thousand, seven hundred forty-nine".