261121325 has 6 divisors (see below), whose sum is σ = 323790474. Its totient is φ = 208897040.

The previous prime is 261121291. The next prime is 261121337. The reversal of 261121325 is 523121162.

261121325 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 17355556 + 243765769 = 4166^2 + 15613^2 .

It is not a de Polignac number, because 261121325 - 2¹⁴ = 261104941 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 261121325.

It is a congruent number.

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, 5222402 + ... + 5222451.

It is an arithmetic number, because the mean of its divisors is an integer number (53965079).

Almost surely, 2^261121325 is an apocalyptic number.

261121325 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

261121325 is a deficient number, since it is larger than the sum of its proper divisors (62669149).

261121325 is a wasteful number, since it uses less digits than its factorization.

261121325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10444863 (or 10444858 counting only the distinct ones).

The product of its digits is 720, while the sum is 23.

The square root of 261121325 is about 16159.2488996240. The cubic root of 261121325 is about 639.1666603395.

Adding to 261121325 its reverse (523121162), we get a palindrome (784242487).

The spelling of 261121325 in words is "two hundred sixty-one million, one hundred twenty-one thousand, three hundred twenty-five".