500001021 has 24 divisors (see below), whose sum is σ = 786534840. Its totient is φ = 304229376.

The previous prime is 500001001. The next prime is 500001023. The reversal of 500001021 is 120100005.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 11148921 + 488852100 = 3339^2 + 22110^2 .

It is not a de Polignac number, because 500001021 - 2⁵ = 500000989 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 500000994 and 500001012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (500001023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13596 + ... + 34421.

It is an arithmetic number, because the mean of its divisors is an integer number (32772285).

Almost surely, 2^500001021 is an apocalyptic number.

It is an amenable number.

500001021 is a deficient number, since it is larger than the sum of its proper divisors (286533819).

500001021 is a wasteful number, since it uses less digits than its factorization.

500001021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48125 (or 48122 counting only the distinct ones).

The product of its (nonzero) digits is 10, while the sum is 9.

The square root of 500001021 is about 22360.7026052403. The cubic root of 500001021 is about 793.7010662292.

Adding to 500001021 its reverse (120100005), we get a palindrome (620101026).

The spelling of 500001021 in words is "five hundred million, one thousand, twenty-one".