51912391 has 2 divisors, whose sum is σ = 51912392. Its totient is φ = 51912390.

The previous prime is 51912379. The next prime is 51912397. The reversal of 51912391 is 19321915.

It is a happy number.

51912391 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51912391 - 2⁵ = 51912359 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51912397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25956195 + 25956196.

It is an arithmetic number, because the mean of its divisors is an integer number (25956196).

Almost surely, 2^51912391 is an apocalyptic number.

51912391 is a deficient number, since it is larger than the sum of its proper divisors (1).

51912391 is an equidigital number, since it uses as much as digits as its factorization.

51912391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2430, while the sum is 31.

The square root of 51912391 is about 7205.0253989837. The cubic root of 51912391 is about 373.0413814607.

The spelling of 51912391 in words is "fifty-one million, nine hundred twelve thousand, three hundred ninety-one".