261840723 has 8 divisors (see below), whose sum is σ = 355708368. Its totient is φ = 171266784.

The previous prime is 261840721. The next prime is 261840737. The reversal of 261840723 is 327048162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 261840723 - 2¹ = 261840721 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261840721) 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, 823240 + ... + 823557.

It is an arithmetic number, because the mean of its divisors is an integer number (44463546).

Almost surely, 2^261840723 is an apocalyptic number.

261840723 is a deficient number, since it is larger than the sum of its proper divisors (93867645).

261840723 is a wasteful number, since it uses less digits than its factorization.

261840723 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1646853.

The product of its (nonzero) digits is 16128, while the sum is 33.

The square root of 261840723 is about 16181.4932252867. The cubic root of 261840723 is about 639.7530973064.

Adding to 261840723 its reverse (327048162), we get a palindrome (588888885).

The spelling of 261840723 in words is "two hundred sixty-one million, eight hundred forty thousand, seven hundred twenty-three".