51516780 has 96 divisors (see below), whose sum is σ = 172053504. Its totient is φ = 11261184.

The previous prime is 51516739. The next prime is 51516781. The reversal of 51516780 is 8761515.

It is not an unprimeable number, because it can be changed into a prime (51516781) 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 31 ways as a sum of consecutive naturals, for example, 6994 + ... + 12326.

It is an arithmetic number, because the mean of its divisors is an integer number (1792224).

Almost surely, 2^51516780 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51516780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86026752).

51516780 is an abundant number, since it is smaller than the sum of its proper divisors (120536724).

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

51516780 is a wasteful number, since it uses less digits than its factorization.

51516780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5375 (or 5373 counting only the distinct ones).

The product of its (nonzero) digits is 8400, while the sum is 33.

The square root of 51516780 is about 7177.5190699851. The cubic root of 51516780 is about 372.0913465119.

The spelling of 51516780 in words is "fifty-one million, five hundred sixteen thousand, seven hundred eighty".