51005439 has 12 divisors (see below), whose sum is σ = 75388456. Its totient is φ = 33212592.

The previous prime is 51005429. The next prime is 51005473. The reversal of 51005439 is 93450015.

It is not a de Polignac number, because 51005439 - 2⁹ = 51004927 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 (51005429) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 65512 + ... + 66285.

Almost surely, 2^51005439 is an apocalyptic number.

51005439 is a deficient number, since it is larger than the sum of its proper divisors (24383017).

51005439 is a wasteful number, since it uses less digits than its factorization.

51005439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131846 (or 131843 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 27.

The square root of 51005439 is about 7141.8092245593. The cubic root of 51005439 is about 370.8561595623.

The spelling of 51005439 in words is "fifty-one million, five thousand, four hundred thirty-nine".