1575 has 18 divisors (see below), whose sum is σ = 3224. Its totient is φ = 720.

The previous prime is 1571. The next prime is 1579. The reversal of 1575 is 5751.

Multipling 1575 by its product of digits (175), we get a square (275625 = 525^{2}).

It can be divided in two parts, 1 and 575, that added together give a square (576 = 24^{2}).

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1571) and next prime (1579).

Together with 1648 it forms a betrothed pair.

It is not a de Polignac number, because 1575 - 2^{2} = 1571 is a prime.

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

It is a Duffinian number.

It is a partition number, being equal to the number of ways a set of 24 identical objects can be partitioned into subset.

1575 is a lucky number.

It is a nialpdrome in base 7, base 13 and base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1571) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 222 + ... + 228.

1575 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1575 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1612).

1575 is a wasteful number, since it uses less digits than its factorization.

1575 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23 (or 15 counting only the distinct ones).

The product of its digits is 175, while the sum is 18.

The square root of 1575 is about 39.6862696660. The cubic root of 1575 is about 11.6348338573.

The spelling of 1575 in words is "one thousand, five hundred seventy-five".

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