257121 has 16 divisors (see below), whose sum is σ = 388800. Its totient is φ = 167904.

The previous prime is 257107. The next prime is 257123. The reversal of 257121 is 121752.

It is not a de Polignac number, because 257121 - 2⁹ = 256609 is a prime.

It is a super-2 number, since 2×257121² = 132222417282, which contains 22 as substring.

It is a Curzon number.

It is a plaindrome in base 14.

It is a junction number, because it is equal to n+sod(n) for n = 257094 and 257103.

It is not an unprimeable number, because it can be changed into a prime (257123) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2350 + ... + 2456.

It is an arithmetic number, because the mean of its divisors is an integer number (24300).

2²⁵⁷¹²¹ is an apocalyptic number.

257121 is the 321-st heptagonal number.

It is an amenable number.

257121 is a deficient number, since it is larger than the sum of its proper divisors (131679).

257121 is a wasteful number, since it uses less digits than its factorization.

257121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205 (or 199 counting only the distinct ones).

The product of its digits is 140, while the sum is 18.

The square root of 257121 is about 507.0710009456. The cubic root of 257121 is about 63.5885881981.

Adding to 257121 its reverse (121752), we get a palindrome (378873).

It can be divided in two parts, 257 and 121, that added together give a triangular number (378 = T₂₇).

The spelling of 257121 in words is "two hundred fifty-seven thousand, one hundred twenty-one".