908138521 has 8 divisors (see below), whose sum is σ = 992577024. Its totient is φ = 827146560.

The previous prime is 908138507. The next prime is 908138531. The reversal of 908138521 is 125831809.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 908138521 - 2¹³ = 908130329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (908138531) 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 7 ways as a sum of consecutive naturals, for example, 861085 + ... + 862138.

It is an arithmetic number, because the mean of its divisors is an integer number (124072128).

Almost surely, 2^908138521 is an apocalyptic number.

It is an amenable number.

908138521 is a deficient number, since it is larger than the sum of its proper divisors (84438503).

908138521 is a wasteful number, since it uses less digits than its factorization.

908138521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1723271.

The product of its (nonzero) digits is 17280, while the sum is 37.

The square root of 908138521 is about 30135.3367494043. The cubic root of 908138521 is about 968.3908989891.

The spelling of 908138521 in words is "nine hundred eight million, one hundred thirty-eight thousand, five hundred twenty-one".