521138 has 4 divisors (see below), whose sum is σ = 781710. Its totient is φ = 260568.

The previous prime is 521137. The next prime is 521153. The reversal of 521138 is 831125.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 508369 + 12769 = 713^2 + 113^2 .

It is not an unprimeable number, because it can be changed into a prime (521137) 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 as a sum of consecutive naturals, namely, 130283 + ... + 130286.

2⁵²¹¹³⁸ is an apocalyptic number.

521138 is a deficient number, since it is larger than the sum of its proper divisors (260572).

521138 is a wasteful number, since it uses less digits than its factorization.

521138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260571.

The product of its digits is 240, while the sum is 20.

The square root of 521138 is about 721.8988848862. The cubic root of 521138 is about 80.4731337889.

The spelling of 521138 in words is "five hundred twenty-one thousand, one hundred thirty-eight".