51954781 has 2 divisors, whose sum is σ = 51954782. Its totient is φ = 51954780.

The previous prime is 51954779. The next prime is 51954817. The reversal of 51954781 is 18745915.

It is a happy number.

Together with next prime (51954817) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30702681 + 21252100 = 5541^2 + 4610^2 .

It is a cyclic number.

It is not a de Polignac number, because 51954781 - 2¹ = 51954779 is a prime.

It is a super-2 number, since 2×51954781² = 5398598537515922, which contains 22 as substring.

Together with 51954779, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51954181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25977390 + 25977391.

It is an arithmetic number, because the mean of its divisors is an integer number (25977391).

Almost surely, 2^51954781 is an apocalyptic number.

It is an amenable number.

51954781 is a deficient number, since it is larger than the sum of its proper divisors (1).

51954781 is an equidigital number, since it uses as much as digits as its factorization.

51954781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 50400, while the sum is 40.

The square root of 51954781 is about 7207.9664954826. The cubic root of 51954781 is about 373.1428917271.

The spelling of 51954781 in words is "fifty-one million, nine hundred fifty-four thousand, seven hundred eighty-one".