781225 has 6 divisors (see below), whose sum is σ = 968750. Its totient is φ = 624960.

The previous prime is 781217. The next prime is 781229. The reversal of 781225 is 522187.

It can be written as a sum of positive squares in 3 ways, for example, as 80656 + 700569 = 284^2 + 837^2 .

It is not a de Polignac number, because 781225 - 2³ = 781217 is a prime.

It is a super-2 number, since 2×781225² = 1220625001250, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (25), and also a Moran number because the ratio is a prime number: 31249 = 781225 / (7 + 8 + 1 + 2 + 2 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 781225.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (781229) 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 5 ways as a sum of consecutive naturals, for example, 15600 + ... + 15649.

781225 is a Friedman number, since it can be written as 2*(5^8+1)-27, using all its digits and the basic arithmetic operations.

2⁷⁸¹²²⁵ is an apocalyptic number.

It is an amenable number.

781225 is a deficient number, since it is larger than the sum of its proper divisors (187525).

781225 is a wasteful number, since it uses less digits than its factorization.

781225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31259 (or 31254 counting only the distinct ones).

The product of its digits is 1120, while the sum is 25.

The square root of 781225 is about 883.8693342344. The cubic root of 781225 is about 92.0998050471.

The spelling of 781225 in words is "seven hundred eighty-one thousand, two hundred twenty-five".