2643257 has 4 divisors (see below), whose sum is σ = 2679540. Its totient is φ = 2606976.

The previous prime is 2643247. The next prime is 2643283. The reversal of 2643257 is 7523462.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7523462 = 2 ⋅3761731.

It can be written as a sum of positive squares in 2 ways, for example, as 942841 + 1700416 = 971^2 + 1304^2 .

It is not a de Polignac number, because 2643257 - 2⁴ = 2643241 is a prime.

It is an Ulam number.

It is a d-powerful number, because it can be written as 2⁸ + 6 + 4³ + 3¹³ + 2²⁰ + 5² + 7 .

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2643227) 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, 18032 + ... + 18177.

It is an arithmetic number, because the mean of its divisors is an integer number (669885).

2^2643257 is an apocalyptic number.

It is an amenable number.

2643257 is a deficient number, since it is larger than the sum of its proper divisors (36283).

2643257 is an equidigital number, since it uses as much as digits as its factorization.

2643257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36282.

The product of its digits is 10080, while the sum is 29.

The square root of 2643257 is about 1625.8096444541. The cubic root of 2643257 is about 138.2652777290.

The spelling of 2643257 in words is "two million, six hundred forty-three thousand, two hundred fifty-seven".