2021851225 has 45 divisors (see below), whose sum is σ = 2784303037. Its totient is φ = 1456146560.

The previous prime is 2021851213. The next prime is 2021851231. The reversal of 2021851225 is 5221581202.

The square root of 2021851225 is 44965.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 47293129 + 1974558096 = 6877^2 + 44436^2 .

It is not a de Polignac number, because 2021851225 - 2¹¹ = 2021849177 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2021851193 and 2021851202.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 87906564 + ... + 87906586.

Almost surely, 2^2021851225 is an apocalyptic number.

2021851225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

2021851225 is the 44965-th square number.

2021851225 is the 22483-rd centered octagonal number.

It is an amenable number.

2021851225 is a deficient number, since it is larger than the sum of its proper divisors (762451812).

2021851225 is an frugal number, since it uses more digits than its factorization.

2021851225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136 (or 45 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 28.

The cubic root of 2021851225 is about 1264.4929097016.

The spelling of 2021851225 in words is "two billion, twenty-one million, eight hundred fifty-one thousand, two hundred twenty-five".