261577040 has 20 divisors (see below), whose sum is σ = 608166804. Its totient is φ = 104630784.

The previous prime is 261577027. The next prime is 261577051. The reversal of 261577040 is 40775162.

It can be written as a sum of positive squares in 2 ways, for example, as 40043584 + 221533456 = 6328^2 + 14884^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 261576988 and 261577006.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1634777 + ... + 1634936.

Almost surely, 2^261577040 is an apocalyptic number.

261577040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261577040 is an abundant number, since it is smaller than the sum of its proper divisors (346589764).

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

261577040 is a wasteful number, since it uses less digits than its factorization.

261577040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3269726 (or 3269720 counting only the distinct ones).

The product of its (nonzero) digits is 11760, while the sum is 32.

The square root of 261577040 is about 16173.3435009586. The cubic root of 261577040 is about 639.5382737398.

The spelling of 261577040 in words is "two hundred sixty-one million, five hundred seventy-seven thousand, forty".