51818512172 has 12 divisors (see below), whose sum is σ = 103637024400. Its totient is φ = 22207933776.

The previous prime is 51818512121. The next prime is 51818512177. The reversal of 51818512172 is 27121581815.

It is a happy number.

51818512172 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (51818512177) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 925330547 + ... + 925330602.

It is an arithmetic number, because the mean of its divisors is an integer number (8636418700).

Almost surely, 2^51818512172 is an apocalyptic number.

It is an amenable number.

51818512172 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

51818512172 is a wasteful number, since it uses less digits than its factorization.

51818512172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1850661160 (or 1850661158 counting only the distinct ones).

The product of its digits is 44800, while the sum is 41.

The spelling of 51818512172 in words is "fifty-one billion, eight hundred eighteen million, five hundred twelve thousand, one hundred seventy-two".