51258391 has 4 divisors (see below), whose sum is σ = 51287632. Its totient is φ = 51229152.

The previous prime is 51258373. The next prime is 51258397. The reversal of 51258391 is 19385215.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19385215 = 5 ⋅3877043.

It is a cyclic number.

It is not a de Polignac number, because 51258391 - 2⁵ = 51258359 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51258397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11811 + ... + 15556.

It is an arithmetic number, because the mean of its divisors is an integer number (12821908).

Almost surely, 2^51258391 is an apocalyptic number.

51258391 is a deficient number, since it is larger than the sum of its proper divisors (29241).

51258391 is a wasteful number, since it uses less digits than its factorization.

51258391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29240.

The product of its digits is 10800, while the sum is 34.

The square root of 51258391 is about 7159.4965605132. The cubic root of 51258391 is about 371.4682129640.

The spelling of 51258391 in words is "fifty-one million, two hundred fifty-eight thousand, three hundred ninety-one".