51481881 has 12 divisors (see below), whose sum is σ = 81123120. Its totient is φ = 31201080.

The previous prime is 51481861. The next prime is 51481901. The reversal of 51481881 is 18818415.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (51481861) and next prime (51481901).

It is not a de Polignac number, because 51481881 - 2⁷ = 51481753 is a prime.

It is a super-2 number, since 2×51481881² = 5300768142596322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (51481861) 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 11 ways as a sum of consecutive naturals, for example, 259911 + ... + 260108.

It is an arithmetic number, because the mean of its divisors is an integer number (6760260).

Almost surely, 2^51481881 is an apocalyptic number.

It is an amenable number.

51481881 is a deficient number, since it is larger than the sum of its proper divisors (29641239).

51481881 is a wasteful number, since it uses less digits than its factorization.

51481881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 520036 (or 520033 counting only the distinct ones).

The product of its digits is 10240, while the sum is 36.

The square root of 51481881 is about 7175.0875255986. The cubic root of 51481881 is about 372.0073056144.

The spelling of 51481881 in words is "fifty-one million, four hundred eighty-one thousand, eight hundred eighty-one".