51502813 has 2 divisors, whose sum is σ = 51502814. Its totient is φ = 51502812.

The previous prime is 51502799. The next prime is 51502817. The reversal of 51502813 is 31820515.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39413284 + 12089529 = 6278^2 + 3477^2 .

It is a cyclic number.

It is not a de Polignac number, because 51502813 - 2¹³ = 51494621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51502817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25751406 + 25751407.

It is an arithmetic number, because the mean of its divisors is an integer number (25751407).

Almost surely, 2^51502813 is an apocalyptic number.

It is an amenable number.

51502813 is a deficient number, since it is larger than the sum of its proper divisors (1).

51502813 is an equidigital number, since it uses as much as digits as its factorization.

51502813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 51502813 is about 7176.5460355243. The cubic root of 51502813 is about 372.0577168896.

The spelling of 51502813 in words is "fifty-one million, five hundred two thousand, eight hundred thirteen".