2021531245 has 4 divisors (see below), whose sum is σ = 2425837500. Its totient is φ = 1617224992.

The previous prime is 2021531243. The next prime is 2021531273. The reversal of 2021531245 is 5421351202.

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 1554409476 + 467121769 = 39426^2 + 21613^2 .

It is a cyclic number.

It is not a de Polignac number, because 2021531245 - 2¹ = 2021531243 is a prime.

It is a super-2 number, since 2×2021531245² = 8173177149022500050, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2021531243) 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 3 ways as a sum of consecutive naturals, for example, 202153120 + ... + 202153129.

It is an arithmetic number, because the mean of its divisors is an integer number (606459375).

Almost surely, 2^2021531245 is an apocalyptic number.

It is an amenable number.

2021531245 is a deficient number, since it is larger than the sum of its proper divisors (404306255).

2021531245 is an equidigital number, since it uses as much as digits as its factorization.

2021531245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 404306254.

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 2021531245 is about 44961.4417584668. The cubic root of 2021531245 is about 1264.4261995859.

Adding to 2021531245 its reverse (5421351202), we get a palindrome (7442882447).

The spelling of 2021531245 in words is "two billion, twenty-one million, five hundred thirty-one thousand, two hundred forty-five".