261957 has 8 divisors (see below), whose sum is σ = 361440. Its totient is φ = 168560.

The previous prime is 261917. The next prime is 261959. The reversal of 261957 is 759162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261957 - 2¹² = 257861 is a prime.

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 261957.

It is not an unprimeable number, because it can be changed into a prime (261959) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1419 + ... + 1592.

It is an arithmetic number, because the mean of its divisors is an integer number (45180).

2²⁶¹⁹⁵⁷ is an apocalyptic number.

It is an amenable number.

261957 is a deficient number, since it is larger than the sum of its proper divisors (99483).

261957 is a wasteful number, since it uses less digits than its factorization.

261957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3043.

The product of its digits is 3780, while the sum is 30.

The square root of 261957 is about 511.8173502335. The cubic root of 261957 is about 63.9847782810.

The spelling of 261957 in words is "two hundred sixty-one thousand, nine hundred fifty-seven".