2578 has 4 divisors (see below), whose sum is σ = 3870.
Its totient is φ = 1288.
The previous prime is 2557. The next prime is 2579. The reversal of 2578 is 8752.
2578 is an esthetic number in base 13, because in such base its adjacent digits differ by 1.
It is a semiprime because it is the product of two primes.
It can be written as a sum of positive squares in only one way, i.e., 1849 + 729 = 43^2 + 27^2
It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.
It is a plaindrome in base 10, base 12 and base 13.
It is a nialpdrome in base 14.
It is not an unprimeable number, because it can be changed into a prime (2579) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 643 + ... + 646.
2578 is a deficient number, since it is larger than the sum of its proper divisors (1292).
2578 is a wasteful number, since it uses less digits than its factorization.
2578 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 1291.
The product of its digits is 560, while the sum is 22.
The square root of 2578 is about 50.7740090991.
The cubic root of 2578 is about 13.7117947692.
Subtracting from 2578 its sum of digits (22), we obtain a triangular number (2556 = T71).
It can be divided in two parts, 2 and 578, that multiplied together give a square (1156 = 342).
The spelling of 2578 in words is "two thousand, five hundred seventy-eight".