261020225 has 6 divisors (see below), whose sum is σ = 323665110. Its totient is φ = 208816160.

The previous prime is 261020197. The next prime is 261020257. The reversal of 261020225 is 522020162.

It can be written as a sum of positive squares in 3 ways, for example, as 2582449 + 258437776 = 1607^2 + 16076^2 .

It is not a de Polignac number, because 261020225 - 2⁶ = 261020161 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261020197 and 261020206.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5220380 + ... + 5220429.

It is an arithmetic number, because the mean of its divisors is an integer number (53944185).

Almost surely, 2^261020225 is an apocalyptic number.

261020225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

261020225 is a deficient number, since it is larger than the sum of its proper divisors (62644885).

261020225 is a wasteful number, since it uses less digits than its factorization.

261020225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10440819 (or 10440814 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 261020225 is about 16156.1203573135. The cubic root of 261020225 is about 639.0841596208.

Adding to 261020225 its reverse (522020162), we get a palindrome (783040387).

The spelling of 261020225 in words is "two hundred sixty-one million, twenty thousand, two hundred twenty-five".