51155281 has 2 divisors, whose sum is σ = 51155282. Its totient is φ = 51155280.

The previous prime is 51155257. The next prime is 51155297. The reversal of 51155281 is 18255115.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 35820225 + 15335056 = 5985^2 + 3916^2 .

It is a cyclic number.

It is not a de Polignac number, because 51155281 - 2⁹ = 51154769 is a prime.

It is a super-2 number, since 2×51155281² = 5233725548377922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51155081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25577640 + 25577641.

It is an arithmetic number, because the mean of its divisors is an integer number (25577641).

Almost surely, 2^51155281 is an apocalyptic number.

It is an amenable number.

51155281 is a deficient number, since it is larger than the sum of its proper divisors (1).

51155281 is an equidigital number, since it uses as much as digits as its factorization.

51155281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2000, while the sum is 28.

The square root of 51155281 is about 7152.2920102580. The cubic root of 51155281 is about 371.2189672769.

The spelling of 51155281 in words is "fifty-one million, one hundred fifty-five thousand, two hundred eighty-one".