520202021 has 4 divisors (see below), whose sum is σ = 520831872. Its totient is φ = 519572172.

The previous prime is 520201999. The next prime is 520202047. The reversal of 520202021 is 120202025.

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.

It is a cyclic number.

It is not a de Polignac number, because 520202021 - 2²² = 516007717 is a prime.

It is a super-2 number, since 2×520202021² = 541220285304968882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 520201987 and 520202005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (520202051) 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, 313685 + ... + 315338.

It is an arithmetic number, because the mean of its divisors is an integer number (130207968).

Almost surely, 2^520202021 is an apocalyptic number.

It is an amenable number.

520202021 is a deficient number, since it is larger than the sum of its proper divisors (629851).

520202021 is an equidigital number, since it uses as much as digits as its factorization.

520202021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 629850.

The product of its (nonzero) digits is 80, while the sum is 14.

The square root of 520202021 is about 22807.9376752919. The cubic root of 520202021 is about 804.2492755475.

Adding to 520202021 its reverse (120202025), we get a palindrome (640404046).

The spelling of 520202021 in words is "five hundred twenty million, two hundred two thousand, twenty-one".