39490909 has 4 divisors (see below), whose sum is σ = 39615804. Its totient is φ = 39366016.

The previous prime is 39490907. The next prime is 39490961. The reversal of 39490909 is 90909493.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90909493 = 3119 ⋅29147.

It can be written as a sum of positive squares in 2 ways, for example, as 15578809 + 23912100 = 3947^2 + 4890^2 .

It is a cyclic number.

It is not a de Polignac number, because 39490909 - 2¹ = 39490907 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 (39490907) 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, 61972 + ... + 62605.

It is an arithmetic number, because the mean of its divisors is an integer number (9903951).

Almost surely, 2^39490909 is an apocalyptic number.

It is an amenable number.

39490909 is a deficient number, since it is larger than the sum of its proper divisors (124895).

39490909 is a wasteful number, since it uses less digits than its factorization.

39490909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124894.

The product of its (nonzero) digits is 78732, while the sum is 43.

The square root of 39490909 is about 6284.1792622426. The cubic root of 39490909 is about 340.5381012117.

The spelling of 39490909 in words is "thirty-nine million, four hundred ninety thousand, nine hundred nine".