900521 has 4 divisors (see below), whose sum is σ = 912000. Its totient is φ = 889044.

The previous prime is 900511. The next prime is 900539. The reversal of 900521 is 125009.

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: 125009 = 41 ⋅3049.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-900521 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 900521.

It is not an unprimeable number, because it can be changed into a prime (900511) 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 in 3 ways as a sum of consecutive naturals, for example, 5621 + ... + 5778.

It is an arithmetic number, because the mean of its divisors is an integer number (228000).

2⁹⁰⁰⁵²¹ is an apocalyptic number.

It is an amenable number.

900521 is a deficient number, since it is larger than the sum of its proper divisors (11479).

900521 is a wasteful number, since it uses less digits than its factorization.

900521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11478.

The product of its (nonzero) digits is 90, while the sum is 17.

The square root of 900521 is about 948.9578494327. The cubic root of 900521 is about 96.5675652360.

The spelling of 900521 in words is "nine hundred thousand, five hundred twenty-one".