2021561025 has 24 divisors (see below), whose sum is σ = 3646162464. Its totient is φ = 980150400.

The previous prime is 2021560997. The next prime is 2021561027. The reversal of 2021561025 is 5201651202.

It is a happy number.

2021561025 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2021561025 - 2¹¹ = 2021558977 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2021560986 and 2021561004.

It is not an unprimeable number, because it can be changed into a prime (2021561027) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1224364 + ... + 1226013.

It is an arithmetic number, because the mean of its divisors is an integer number (151923436).

Almost surely, 2^2021561025 is an apocalyptic number.

2021561025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

2021561025 is a deficient number, since it is larger than the sum of its proper divisors (1624601439).

2021561025 is a wasteful number, since it uses less digits than its factorization.

2021561025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2450401 (or 2450396 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 24.

The square root of 2021561025 is about 44961.7729299012. The cubic root of 2021561025 is about 1264.4324084811.

The spelling of 2021561025 in words is "two billion, twenty-one million, five hundred sixty-one thousand, twenty-five".