261423 has 12 divisors (see below), whose sum is σ = 390208. Its totient is φ = 168480.

The previous prime is 261407. The next prime is 261427. The reversal of 261423 is 324162.

It is a happy number.

It is not a de Polignac number, because 261423 - 2⁴ = 261407 is a prime.

It is a Duffinian number.

261423 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 261396 and 261405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261427) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 190 + ... + 747.

2²⁶¹⁴²³ is an apocalyptic number.

261423 is a deficient number, since it is larger than the sum of its proper divisors (128785).

261423 is a wasteful number, since it uses less digits than its factorization.

261423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 974 (or 971 counting only the distinct ones).

The product of its digits is 288, while the sum is 18.

The square root of 261423 is about 511.2954136309. The cubic root of 261423 is about 63.9412709941.

Adding to 261423 its reverse (324162), we get a palindrome (585585).

It can be divided in two parts, 2 and 61423, that added together give a triangular number (61425 = T₃₅₀).

The spelling of 261423 in words is "two hundred sixty-one thousand, four hundred twenty-three".