261089743 has 4 divisors (see below), whose sum is σ = 261829728. Its totient is φ = 260349760.

The previous prime is 261089729. The next prime is 261089749. The reversal of 261089743 is 347980162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 347980162 = 2 ⋅173990081.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261089743 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 261089696 and 261089705.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261089749) 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, 369463 + ... + 370168.

It is an arithmetic number, because the mean of its divisors is an integer number (65457432).

Almost surely, 2^261089743 is an apocalyptic number.

261089743 is a deficient number, since it is larger than the sum of its proper divisors (739985).

261089743 is an equidigital number, since it uses as much as digits as its factorization.

261089743 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 739984.

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 261089743 is about 16158.2716588130. The cubic root of 261089743 is about 639.1408907407.

The spelling of 261089743 in words is "two hundred sixty-one million, eighty-nine thousand, seven hundred forty-three".