39640249 has 4 divisors (see below), whose sum is σ = 43243920. Its totient is φ = 36036580.

The previous prime is 39640217. The next prime is 39640253. The reversal of 39640249 is 94204693.

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, and also an emirpimes, since its reverse is a distinct semiprime: 94204693 = 11 ⋅8564063.

It is a cyclic number.

It is not a de Polignac number, because 39640249 - 2⁵ = 39640217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (39640259) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1801819 + ... + 1801840.

It is an arithmetic number, because the mean of its divisors is an integer number (10810980).

Almost surely, 2^39640249 is an apocalyptic number.

It is an amenable number.

39640249 is a deficient number, since it is larger than the sum of its proper divisors (3603671).

39640249 is a wasteful number, since it uses less digits than its factorization.

39640249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3603670.

The product of its (nonzero) digits is 46656, while the sum is 37.

The square root of 39640249 is about 6296.0502698120. The cubic root of 39640249 is about 340.9668242564.

The spelling of 39640249 in words is "thirty-nine million, six hundred forty thousand, two hundred forty-nine".