261511122 has 16 divisors (see below), whose sum is σ = 535186080. Its totient is φ = 85143072.

The previous prime is 261511091. The next prime is 261511139. The reversal of 261511122 is 221115162.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 506547 + ... + 507062.

It is an arithmetic number, because the mean of its divisors is an integer number (33449130).

Almost surely, 2^261511122 is an apocalyptic number.

261511122 is an abundant number, since it is smaller than the sum of its proper divisors (273674958).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261511122 is a wasteful number, since it uses less digits than its factorization.

261511122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1013657.

The product of its digits is 240, while the sum is 21.

The square root of 261511122 is about 16171.3055131613. The cubic root of 261511122 is about 639.4845475340.

Adding to 261511122 its reverse (221115162), we get a palindrome (482626284).

The spelling of 261511122 in words is "two hundred sixty-one million, five hundred eleven thousand, one hundred twenty-two".