51001 has 2 divisors, whose sum is σ = 51002. Its totient is φ = 51000.

The previous prime is 50993. The next prime is 51031. The reversal of 51001 is 10015.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 48400 + 2601 = 220^2 + 51^2 .

It is a cyclic number.

It is not a de Polignac number, because 51001 - 2³ = 50993 is a prime.

It is a super-2 number, since 2×51001² = 5202204002, which contains 22 as substring.

51001 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (51031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25500 + 25501.

It is an arithmetic number, because the mean of its divisors is an integer number (25501).

2⁵¹⁰⁰¹ is an apocalyptic number.

It is an amenable number.

51001 is a deficient number, since it is larger than the sum of its proper divisors (1).

51001 is an equidigital number, since it uses as much as digits as its factorization.

51001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5, while the sum is 7.

The square root of 51001 is about 225.8340098391. The cubic root of 51001 is about 37.0845400721.

Adding to 51001 its reverse (10015), we get a palindrome (61016).

It can be divided in two parts, 5 and 1001, that multiplied together give a palindrome (5005).

The spelling of 51001 in words is "fifty-one thousand, one".