51660361 has 2 divisors, whose sum is σ = 51660362. Its totient is φ = 51660360.

The previous prime is 51660359. The next prime is 51660377. The reversal of 51660361 is 16306615.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35176761 + 16483600 = 5931^2 + 4060^2 .

It is a cyclic number.

It is not a de Polignac number, because 51660361 - 2¹ = 51660359 is a prime.

Together with 51660359, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (51630361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25830180 + 25830181.

It is an arithmetic number, because the mean of its divisors is an integer number (25830181).

Almost surely, 2^51660361 is an apocalyptic number.

It is an amenable number.

51660361 is a deficient number, since it is larger than the sum of its proper divisors (1).

51660361 is an equidigital number, since it uses as much as digits as its factorization.

51660361 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3240, while the sum is 28.

The square root of 51660361 is about 7187.5142434641. The cubic root of 51660361 is about 372.4367077126.

Adding to 51660361 its reverse (16306615), we get a palindrome (67966976).

The spelling of 51660361 in words is "fifty-one million, six hundred sixty thousand, three hundred sixty-one".