261536756 has 24 divisors (see below), whose sum is σ = 493584840. Its totient is φ = 120540672.

The previous prime is 261536753. The next prime is 261536771. The reversal of 261536756 is 657635162.

It can be written as a sum of positive squares in 4 ways, for example, as 68326756 + 193210000 = 8266^2 + 13900^2 .

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261536753) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38960 + ... + 45176.

It is an arithmetic number, because the mean of its divisors is an integer number (20566035).

Almost surely, 2^261536756 is an apocalyptic number.

261536756 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

261536756 is a deficient number, since it is larger than the sum of its proper divisors (232048084).

261536756 is a wasteful number, since it uses less digits than its factorization.

261536756 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7043 (or 7041 counting only the distinct ones).

The product of its digits is 226800, while the sum is 41.

The square root of 261536756 is about 16172.0980704422. The cubic root of 261536756 is about 639.5054414972.

The spelling of 261536756 in words is "two hundred sixty-one million, five hundred thirty-six thousand, seven hundred fifty-six".