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BaseRepresentation
bin110101001
3120202
412221
53200
61545
71145
oct651
9522
10425
11357
122b5
13269
14225
151d5
hex1a9

425 has 6 divisors (see below), whose sum is σ = 558. Its totient is φ = 320.

The previous prime is 421. The next prime is 431. The reversal of 425 is 524.

425 is nontrivially palindromic in base 4.

It can be written as a sum of positive squares in 3 ways, for example, as 64 + 361 = 8^2 + 19^2 .

It is a sliding number, since 425 = 25 + 400 and 1/25 + 1/400 = 0.0425.

It is not a de Polignac number, because 425 - 22 = 421 is a prime.

It is a magnanimous number.

It is a Duffinian number.

It is a plaindrome in base 7, base 11, base 13 and base 14.

It is a nialpdrome in base 5, base 8 and base 9.

It is not an unprimeable number, because it can be changed into a prime (421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 17 + ... + 33.

It is an arithmetic number, because the mean of its divisors is an integer number (93).

425 is the 17-th pentagonal number.

It is an amenable number.

425 is a deficient number, since it is larger than the sum of its proper divisors (133).

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

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

The sum of its prime factors is 27 (or 22 counting only the distinct ones).

The product of its digits is 40, while the sum is 11.

The square root of 425 is about 20.6155281281. The cubic root of 425 is about 7.5184729810.

Subtracting from 425 its sum of digits (11), we obtain a palindrome (414).

Adding to 425 its product of digits (40), we get a triangular number (465 = T30).

Adding to 425 its reverse (524), we get a palindrome (949).

Subtracting 425 from its reverse (524), we obtain a palindrome (99).

It can be divided in two parts, 42 and 5, that multiplied together give a triangular number (210 = T20).

The spelling of 425 in words is "four hundred twenty-five", and thus it is an aban number.

Divisors: 1 5 17 25 85 425