5205512021 has 4 divisors (see below), whose sum is σ = 5206285344. Its totient is φ = 5204738700.

The previous prime is 5205511991. The next prime is 5205512027. The reversal of 5205512021 is 1202155025.

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 5205512021 - 2¹⁴ = 5205495637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5205512027) 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, 376475 + ... + 390056.

It is an arithmetic number, because the mean of its divisors is an integer number (1301571336).

Almost surely, 2^5205512021 is an apocalyptic number.

It is an amenable number.

5205512021 is a deficient number, since it is larger than the sum of its proper divisors (773323).

5205512021 is an equidigital number, since it uses as much as digits as its factorization.

5205512021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 773322.

The product of its (nonzero) digits is 1000, while the sum is 23.

The square root of 5205512021 is about 72149.2343757021. The cubic root of 5205512021 is about 1733.0901391504.

Adding to 5205512021 its reverse (1202155025), we get a palindrome (6407667046).

The spelling of 5205512021 in words is "five billion, two hundred five million, five hundred twelve thousand, twenty-one".