261740241 has 40 divisors (see below), whose sum is σ = 451552640. Its totient is φ = 147992832.

The previous prime is 261740239. The next prime is 261740249. The reversal of 261740241 is 142047162.

261740241 is a `hidden beast` number, since 2 + 617 + 4 + 0 + 2 + 41 = 666.

It is not a de Polignac number, because 261740241 - 2¹ = 261740239 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (261740249) 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 39 ways as a sum of consecutive naturals, for example, 52620 + ... + 57378.

It is an arithmetic number, because the mean of its divisors is an integer number (11288816).

Almost surely, 2^261740241 is an apocalyptic number.

261740241 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

261740241 is a deficient number, since it is larger than the sum of its proper divisors (189812399).

261740241 is an equidigital number, since it uses as much as digits as its factorization.

261740241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4875 (or 4866 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 261740241 is about 16178.3880841078. The cubic root of 261740241 is about 639.6712512452.

The spelling of 261740241 in words is "two hundred sixty-one million, seven hundred forty thousand, two hundred forty-one".