261745723 has 4 divisors (see below), whose sum is σ = 265059040. Its totient is φ = 258432408.

The previous prime is 261745721. The next prime is 261745739. The reversal of 261745723 is 327547162.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 261745723 - 2¹ = 261745721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261745721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1656540 + ... + 1656697.

It is an arithmetic number, because the mean of its divisors is an integer number (66264760).

Almost surely, 2^261745723 is an apocalyptic number.

261745723 is a deficient number, since it is larger than the sum of its proper divisors (3313317).

261745723 is an equidigital number, since it uses as much as digits as its factorization.

261745723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3313316.

The product of its digits is 70560, while the sum is 37.

The square root of 261745723 is about 16178.5575067742. The cubic root of 261745723 is about 639.6757170638.

The spelling of 261745723 in words is "two hundred sixty-one million, seven hundred forty-five thousand, seven hundred twenty-three".