1601 has 2 divisors, whose sum is σ = 1602. Its totient is φ = 1600.

The previous prime is 1597. The next prime is 1607. The reversal of 1601 is 1061.

It is a Cunningham number, because it is equal to 40²+1.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1600 + 1 = 40^2 + 1^2 .

It is an emirp because it is prime and its reverse (1061) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 1091 and 1901.

It is a cyclic number.

It is not a de Polignac number, because 1601 - 2² = 1597 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a plaindrome in base 6, base 7 and base 11.

It is a nialpdrome in base 13 and base 16.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 1601.

It is not a weakly prime, because it can be changed into another prime (1607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 800 + 801.

It is an arithmetic number, because the mean of its divisors is an integer number (801).

It is a Proth number, since it is equal to 25 ⋅ 2⁶ + 1 and 25 < 2⁶.

It is an amenable number.

1601 is a deficient number, since it is larger than the sum of its proper divisors (1).

1601 is an equidigital number, since it uses as much as digits as its factorization.

1601 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6, while the sum is 8.

The square root of 1601 is about 40.0124980475. The cubic root of 1601 is about 11.6985071268.

Adding to 1601 its reverse (1061), we get a palindrome (2662).

It can be divided in two parts, 160 and 1, that added together give a palindrome (161).

The spelling of 1601 in words is "one thousand, six hundred one".