261167140 has 48 divisors (see below), whose sum is σ = 592442928. Its totient is φ = 96136704.

The previous prime is 261167131. The next prime is 261167143. The reversal of 261167140 is 41761162.

It can be written as a sum of positive squares in 8 ways, for example, as 21288996 + 239878144 = 4614^2 + 15488^2 .

It is a junction number, because it is equal to n+sod(n) for n = 261167099 and 261167108.

It is not an unprimeable number, because it can be changed into a prime (261167143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 95634 + ... + 98326.

It is an arithmetic number, because the mean of its divisors is an integer number (12342561).

Almost surely, 2^261167140 is an apocalyptic number.

261167140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261167140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (296221464).

261167140 is an abundant number, since it is smaller than the sum of its proper divisors (331275788).

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

261167140 is a wasteful number, since it uses less digits than its factorization.

261167140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3088 (or 3086 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 261167140 is about 16160.6664466537. Note that the first 3 decimals coincide. The cubic root of 261167140 is about 639.2040397812.

It can be divided in two parts, 2611 and 67140, that added together give a triangular number (69751 = T₃₇₃).

The spelling of 261167140 in words is "two hundred sixty-one million, one hundred sixty-seven thousand, one hundred forty".