It is a semiprime because it is the product of two primes.
It is a cyclic number.
It is a Duffinian number.
It is a plaindrome in base 4, base 8 and base 16.
It is a nialpdrome in base 7 and base 13.
It is a zygodrome in base 4.
It is a congruent number.
21535 is an apocalyptic number.
1535 is an equidigital number, since it uses as much as digits as its factorization.
1535 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 312.
The square root of 1535 is about 39.1790760483. The cubic root of 1535 is about 11.5354921134.
Subtracting from 1535 its sum of digits (14), we obtain a square (1521 = 392).
Adding to 1535 its reverse (5351), we get a palindrome (6886).
The spelling of 1535 in words is "one thousand, five hundred thirty-five".