51520930818 has 32 divisors (see below), whose sum is σ = 117790721664. Its totient is φ = 14716691712.

The previous prime is 51520930817. The next prime is 51520930819. The reversal of 51520930818 is 81803902515.

It is an interprime number because it is at equal distance from previous prime (51520930817) and next prime (51520930819).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 51520930818.

It is not an unprimeable number, because it can be changed into a prime (51520930817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28596 + ... + 322272.

It is an arithmetic number, because the mean of its divisors is an integer number (3680960052).

Almost surely, 2^51520930818 is an apocalyptic number.

51520930818 is an abundant number, since it is smaller than the sum of its proper divisors (66269790846).

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

51520930818 is a wasteful number, since it uses less digits than its factorization.

51520930818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 297866.

The product of its (nonzero) digits is 86400, while the sum is 42.

The spelling of 51520930818 in words is "fifty-one billion, five hundred twenty million, nine hundred thirty thousand, eight hundred eighteen".