51487881 has 16 divisors (see below), whose sum is σ = 69709248. Its totient is φ = 33800000.

The previous prime is 51487873. The next prime is 51487903. The reversal of 51487881 is 18878415.

It is a cyclic number.

It is not a de Polignac number, because 51487881 - 2³ = 51487873 is a prime.

It is a super-2 number, since 2×51487881² = 5302003779740322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (51487861) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 75715 + ... + 76391.

It is an arithmetic number, because the mean of its divisors is an integer number (4356828).

Almost surely, 2^51487881 is an apocalyptic number.

It is an amenable number.

51487881 is a deficient number, since it is larger than the sum of its proper divisors (18221367).

51487881 is a wasteful number, since it uses less digits than its factorization.

51487881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1032.

The product of its digits is 71680, while the sum is 42.

The square root of 51487881 is about 7175.5056267834. The cubic root of 51487881 is about 372.0217570232.

The spelling of 51487881 in words is "fifty-one million, four hundred eighty-seven thousand, eight hundred eighty-one".