10520021 has 4 divisors (see below), whose sum is σ = 10532844. Its totient is φ = 10507200.

The previous prime is 10520017. The next prime is 10520033. The reversal of 10520021 is 12002501.

10520021 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2283121 + 8236900 = 1511^2 + 2870^2 .

It is a cyclic number.

It is not a de Polignac number, because 10520021 - 2² = 10520017 is a prime.

It is a super-2 number, since 2×10520021² = 221341683680882, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 10519984 and 10520011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10520051) 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, 5090 + ... + 6851.

It is an arithmetic number, because the mean of its divisors is an integer number (2633211).

Almost surely, 2^10520021 is an apocalyptic number.

It is an amenable number.

10520021 is a deficient number, since it is larger than the sum of its proper divisors (12823).

10520021 is an equidigital number, since it uses as much as digits as its factorization.

10520021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12822.

The product of its (nonzero) digits is 20, while the sum is 11.

The square root of 10520021 is about 3243.4581853324. The cubic root of 10520021 is about 219.1150469656.

Adding to 10520021 its reverse (12002501), we get a palindrome (22522522).

The spelling of 10520021 in words is "ten million, five hundred twenty thousand, twenty-one".