261457 has 8 divisors (see below), whose sum is σ = 306432. Its totient is φ = 218400.

The previous prime is 261451. The next prime is 261463. The reversal of 261457 is 754162.

It is an interprime number because it is at equal distance from previous prime (261451) and next prime (261463).

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

It is not a de Polignac number, because 261457 - 2⁷ = 261329 is a prime.

261457 is a lucky number.

It is a nialpdrome in base 8.

It is not an unprimeable number, because it can be changed into a prime (261451) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 169 + ... + 742.

It is an arithmetic number, because the mean of its divisors is an integer number (38304).

2²⁶¹⁴⁵⁷ is an apocalyptic number.

It is an amenable number.

261457 is a deficient number, since it is larger than the sum of its proper divisors (44975).

261457 is an equidigital number, since it uses as much as digits as its factorization.

261457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 959.

The product of its digits is 1680, while the sum is 25.

The square root of 261457 is about 511.3286614302. The cubic root of 261457 is about 63.9440428862.

The spelling of 261457 in words is "two hundred sixty-one thousand, four hundred fifty-seven".