261685755 has 32 divisors (see below), whose sum is σ = 468648000. Its totient is φ = 138537216.

The previous prime is 261685747. The next prime is 261685757. The reversal of 261685755 is 557586162.

It is not a de Polignac number, because 261685755 - 2³ = 261685747 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 261685755.

It is not an unprimeable number, because it can be changed into a prime (261685757) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11421 + ... + 25569.

It is an arithmetic number, because the mean of its divisors is an integer number (14645250).

Almost surely, 2^261685755 is an apocalyptic number.

261685755 is a deficient number, since it is larger than the sum of its proper divisors (206962245).

261685755 is a wasteful number, since it uses less digits than its factorization.

261685755 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14300 (or 14294 counting only the distinct ones).

The product of its digits is 504000, while the sum is 45.

The square root of 261685755 is about 16176.7040833416. The cubic root of 261685755 is about 639.6268617564.

The spelling of 261685755 in words is "two hundred sixty-one million, six hundred eighty-five thousand, seven hundred fifty-five".