261701623 has 4 divisors (see below), whose sum is σ = 262148040. Its totient is φ = 261255208.

The previous prime is 261701617. The next prime is 261701633. The reversal of 261701623 is 326107162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 326107162 = 2 ⋅163053581.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261701623 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 261701591 and 261701600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261701633) 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, 222328 + ... + 223501.

It is an arithmetic number, because the mean of its divisors is an integer number (65537010).

Almost surely, 2^261701623 is an apocalyptic number.

261701623 is a deficient number, since it is larger than the sum of its proper divisors (446417).

261701623 is an equidigital number, since it uses as much as digits as its factorization.

261701623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 446416.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 261701623 is about 16177.1945342819. The cubic root of 261701623 is about 639.6397899775.

Adding to 261701623 its reverse (326107162), we get a palindrome (587808785).

The spelling of 261701623 in words is "two hundred sixty-one million, seven hundred one thousand, six hundred twenty-three".