51005503 has 2 divisors, whose sum is σ = 51005504. Its totient is φ = 51005502.

The previous prime is 51005489. The next prime is 51005533. The reversal of 51005503 is 30550015.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51005503 - 2¹⁷ = 50874431 is a prime.

It is a super-2 number, since 2×51005503² = 5203122672566018, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51005533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25502751 + 25502752.

It is an arithmetic number, because the mean of its divisors is an integer number (25502752).

Almost surely, 2^51005503 is an apocalyptic number.

51005503 is a deficient number, since it is larger than the sum of its proper divisors (1).

51005503 is an equidigital number, since it uses as much as digits as its factorization.

51005503 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 375, while the sum is 19.

The square root of 51005503 is about 7141.8137052152. The cubic root of 51005503 is about 370.8563146750.

Adding to 51005503 its reverse (30550015), we get a palindrome (81555518).

The spelling of 51005503 in words is "fifty-one million, five thousand, five hundred three".