51247919 has 2 divisors, whose sum is σ = 51247920. Its totient is φ = 51247918.

The previous prime is 51247837. The next prime is 51247939. The reversal of 51247919 is 91974215.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51247919 - 2¹² = 51243823 is a prime.

It is a super-2 number, since 2×51247919² = 5252698403661122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51247939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25623959 + 25623960.

It is an arithmetic number, because the mean of its divisors is an integer number (25623960).

Almost surely, 2^51247919 is an apocalyptic number.

51247919 is a deficient number, since it is larger than the sum of its proper divisors (1).

51247919 is an equidigital number, since it uses as much as digits as its factorization.

51247919 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22680, while the sum is 38.

The square root of 51247919 is about 7158.7651868182. The cubic root of 51247919 is about 371.4429144715.

The spelling of 51247919 in words is "fifty-one million, two hundred forty-seven thousand, nine hundred nineteen".