51866784 has 96 divisors (see below), whose sum is σ = 152591040. Its totient is φ = 17139456.

The previous prime is 51866767. The next prime is 51866791. The reversal of 51866784 is 48766815.

It is a happy number.

51866784 is a `hidden beast` number, since 518 + 66 + 78 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (96).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 149299 + ... + 149645.

It is an arithmetic number, because the mean of its divisors is an integer number (1589490).

Almost surely, 2^51866784 is an apocalyptic number.

51866784 is a gapful number since it is divisible by the number (54) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51866784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76295520).

51866784 is an abundant number, since it is smaller than the sum of its proper divisors (100724256).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51866784 is a wasteful number, since it uses less digits than its factorization.

51866784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 539 (or 525 counting only the distinct ones).

The product of its digits is 322560, while the sum is 45.

The square root of 51866784 is about 7201.8597598120. The cubic root of 51866784 is about 372.9321057966.

It can be divided in two parts, 51866 and 784, that added together give a triangular number (52650 = T₃₂₄).

The spelling of 51866784 in words is "fifty-one million, eight hundred sixty-six thousand, seven hundred eighty-four".