51380081 has 2 divisors, whose sum is σ = 51380082. Its totient is φ = 51380080.

The previous prime is 51380059. The next prime is 51380107. The reversal of 51380081 is 18008315.

It is an a-pointer prime, because the next prime (51380107) can be obtained adding 51380081 to its sum of digits (26).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46362481 + 5017600 = 6809^2 + 2240^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51380081 is a prime.

It is a super-2 number, since 2×51380081² = 5279825447133122, which contains 22 as substring.

It is a zygodrome in base 9.

It is a self number, because there is not a number n which added to its sum of digits gives 51380081.

It is not a weakly prime, because it can be changed into another prime (51380881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25690040 + 25690041.

It is an arithmetic number, because the mean of its divisors is an integer number (25690041).

Almost surely, 2^51380081 is an apocalyptic number.

It is an amenable number.

51380081 is a deficient number, since it is larger than the sum of its proper divisors (1).

51380081 is an equidigital number, since it uses as much as digits as its factorization.

51380081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 960, while the sum is 26.

The square root of 51380081 is about 7167.9900251047. The cubic root of 51380081 is about 371.7619420550.

Adding to 51380081 its reverse (18008315), we get a palindrome (69388396).

The spelling of 51380081 in words is "fifty-one million, three hundred eighty thousand, eighty-one".