51555789481 has 27 divisors (see below), whose sum is σ = 60648007581. Its totient is φ = 43698866904.

The previous prime is 51555789479. The next prime is 51555789503. The reversal of 51555789481 is 18498755515.

It is a happy number.

The square root of 51555789481 is 227059.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 51555789481 - 2¹ = 51555789479 is a prime.

It is a super-2 number, since 2×51555789481² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (51555789581) 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 26 ways as a sum of consecutive naturals, for example, 259074220 + ... + 259074418.

It is an arithmetic number, because the mean of its divisors is an integer number (2246222503).

Almost surely, 2^51555789481 is an apocalyptic number.

51555789481 is the 227059-th square number.

51555789481 is the 113530-th centered octagonal number.

It is an amenable number.

51555789481 is a deficient number, since it is larger than the sum of its proper divisors (9092218100).

51555789481 is an frugal number, since it uses more digits than its factorization.

51555789481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 738 (or 369 counting only the distinct ones).

The product of its digits is 10080000, while the sum is 58.

The spelling of 51555789481 in words is "fifty-one billion, five hundred fifty-five million, seven hundred eighty-nine thousand, four hundred eighty-one".