820536025 has 27 divisors (see below), whose sum is σ = 1084052919. Its totient is φ = 615982080.

The previous prime is 820536023. The next prime is 820536029. The reversal of 820536025 is 520635028.

It is a happy number.

The square root of 820536025 is 28645.

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

It can be written as a sum of positive squares in 13 ways, for example, as 480354889 + 340181136 = 21917^2 + 18444^2 .

It is not a de Polignac number, because 820536025 - 2¹ = 820536023 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (820536023) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 2434657 + ... + 2434993.

Almost surely, 2^820536025 is an apocalyptic number.

820536025 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

820536025 is the 28645-th square number.

820536025 is the 14323-rd centered octagonal number.

It is an amenable number.

820536025 is a deficient number, since it is larger than the sum of its proper divisors (263516894).

820536025 is an equidigital number, since it uses as much as digits as its factorization.

820536025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 718 (or 359 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 31.

The cubic root of 820536025 is about 936.1940667226.

Multiplying 820536025 by its product of nonzero digits (14400), we get a square (11815718760000 = 3437400²).

The spelling of 820536025 in words is "eight hundred twenty million, five hundred thirty-six thousand, twenty-five".