51516397 has 2 divisors, whose sum is σ = 51516398. Its totient is φ = 51516396.

The previous prime is 51516359. The next prime is 51516403. The reversal of 51516397 is 79361515.

51516397 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41744521 + 9771876 = 6461^2 + 3126^2 .

It is a cyclic number.

It is not a de Polignac number, because 51516397 - 2¹⁵ = 51483629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51516317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25758198 + 25758199.

It is an arithmetic number, because the mean of its divisors is an integer number (25758199).

Almost surely, 2^51516397 is an apocalyptic number.

It is an amenable number.

51516397 is a deficient number, since it is larger than the sum of its proper divisors (1).

51516397 is an equidigital number, since it uses as much as digits as its factorization.

51516397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 28350, while the sum is 37.

The square root of 51516397 is about 7177.4923894073. The cubic root of 51516397 is about 372.0904244089.

The spelling of 51516397 in words is "fifty-one million, five hundred sixteen thousand, three hundred ninety-seven".