261760643 has 4 divisors (see below), whose sum is σ = 263328240. Its totient is φ = 260193048.

The previous prime is 261760601. The next prime is 261760711. The reversal of 261760643 is 346067162.

261760643 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 261760643 - 2⁶ = 261760579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261760043) 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, 783548 + ... + 783881.

It is an arithmetic number, because the mean of its divisors is an integer number (65832060).

Almost surely, 2^261760643 is an apocalyptic number.

261760643 is a deficient number, since it is larger than the sum of its proper divisors (1567597).

261760643 is a wasteful number, since it uses less digits than its factorization.

261760643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1567596.

The product of its (nonzero) digits is 36288, while the sum is 35.

The square root of 261760643 is about 16179.0186043530. The cubic root of 261760643 is about 639.6878710738.

The spelling of 261760643 in words is "two hundred sixty-one million, seven hundred sixty thousand, six hundred forty-three".