261437 has 4 divisors (see below), whose sum is σ = 285216. Its totient is φ = 237660.

The previous prime is 261433. The next prime is 261439. The reversal of 261437 is 734162.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 261437 - 2² = 261433 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 261437.

It is not an unprimeable number, because it can be changed into a prime (261431) 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, 11873 + ... + 11894.

It is an arithmetic number, because the mean of its divisors is an integer number (71304).

2²⁶¹⁴³⁷ is an apocalyptic number.

It is an amenable number.

261437 is a deficient number, since it is larger than the sum of its proper divisors (23779).

261437 is a wasteful number, since it uses less digits than its factorization.

261437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23778.

The product of its digits is 1008, while the sum is 23.

The square root of 261437 is about 511.3091041630. The cubic root of 261437 is about 63.9424123906.

Adding to 261437 its reverse (734162), we get a palindrome (995599).

The spelling of 261437 in words is "two hundred sixty-one thousand, four hundred thirty-seven".