49999909 has 4 divisors (see below), whose sum is σ = 50042016. Its totient is φ = 49957804.

The previous prime is 49999903. The next prime is 49999921. The reversal of 49999909 is 90999994.

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: 90999994 = 2 ⋅45499997.

It is a cyclic number.

It is not a de Polignac number, because 49999909 - 2⁵ = 49999877 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 (49999903) 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, 19219 + ... + 21664.

It is an arithmetic number, because the mean of its divisors is an integer number (12510504).

Almost surely, 2^49999909 is an apocalyptic number.

It is an amenable number.

49999909 is a deficient number, since it is larger than the sum of its proper divisors (42107).

49999909 is a wasteful number, since it uses less digits than its factorization.

49999909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42106.

The product of its (nonzero) digits is 2125764, while the sum is 58.

The square root of 49999909 is about 7071.0613771908. The cubic root of 49999909 is about 368.4029263660.

The spelling of 49999909 in words is "forty-nine million, nine hundred ninety-nine thousand, nine hundred nine".