261577116 has 18 divisors (see below), whose sum is σ = 661208912. Its totient is φ = 87192360.

The previous prime is 261577111. The next prime is 261577133. The reversal of 261577116 is 611775162.

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×261577116² = 136845175229754912, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 7266031 = 261577116 / (2 + 6 + 1 + 5 + 7 + 7 + 1 + 1 + 6).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261577111) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 3632980 + ... + 3633051.

Almost surely, 2^261577116 is an apocalyptic number.

It is an amenable number.

261577116 is an abundant number, since it is smaller than the sum of its proper divisors (399631796).

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

261577116 is a wasteful number, since it uses less digits than its factorization.

261577116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7266041 (or 7266036 counting only the distinct ones).

The product of its digits is 17640, while the sum is 36.

The square root of 261577116 is about 16173.3458505035. The cubic root of 261577116 is about 639.5383356781.

The spelling of 261577116 in words is "two hundred sixty-one million, five hundred seventy-seven thousand, one hundred sixteen".