261607 has 4 divisors (see below), whose sum is σ = 263736. Its totient is φ = 259480.

The previous prime is 261601. The next prime is 261619. The reversal of 261607 is 706162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 706162 = 2 ⋅353081.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261607 is a prime.

It is a Duffinian number.

261607 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261601) 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, 868 + ... + 1129.

It is an arithmetic number, because the mean of its divisors is an integer number (65934).

2²⁶¹⁶⁰⁷ is an apocalyptic number.

261607 is a deficient number, since it is larger than the sum of its proper divisors (2129).

261607 is a wasteful number, since it uses less digits than its factorization.

261607 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2128.

The product of its (nonzero) digits is 504, while the sum is 22.

The square root of 261607 is about 511.4753170975. The cubic root of 261607 is about 63.9562689536.

Adding to 261607 its reverse (706162), we get a palindrome (967769).

It can be divided in two parts, 261 and 607, that added together give a palindrome (868).

The spelling of 261607 in words is "two hundred sixty-one thousand, six hundred seven".