Search a number
BaseRepresentation
bin10000000001
31101222
4100001
513100
64425
72663
oct2001
91358
101025
11852
12715
1360b
14533
15485
hex401

1025 has 6 divisors (see below), whose sum is σ = 1302. Its totient is φ = 800.

The previous prime is 1021. The next prime is 1031. The reversal of 1025 is 5201.

Adding to 1025 its product of nonzero digits (10), we get a triangular number (1035 = T45).

Adding to 1025 its reverse (5201), we get a palindrome (6226).

1025 is nontrivially palindromic in base 2 and base 4.

It is a Cunningham number, because it is equal to 210+1.

It can be written as a sum of positive squares in 3 ways, for example, as 1 + 1024 = 1^2 + 32^2 .

It is not a de Polignac number, because 1025 - 22 = 1021 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a plaindrome in base 9.

It is a nialpdrome in base 11 and base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (2) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5 + ... + 45.

It is an arithmetic number, because the mean of its divisors is an integer number (217).

It is a Proth number, since it is equal to 1 ⋅ 210 + 1 and 1 < 210.

It is an amenable number.

1025 is a deficient number, since it is larger than the sum of its proper divisors (277).

1025 is an equidigital number, since it uses as much as digits as its factorization.

1025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51 (or 46 counting only the distinct ones).

The product of its (nonzero) digits is 10, while the sum is 8.

The square root of 1025 is about 32.0156211872. The cubic root of 1025 is about 10.0826483761.

The spelling of 1025 in words is "one thousand, twenty-five".

Divisors: 1 5 25 41 205 1025