51113255520 has 96 divisors (see below), whose sum is σ = 161056782432. Its totient is φ = 13625966592.

The previous prime is 51113255519. The next prime is 51113255527. The reversal of 51113255520 is 2555231115.

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

It is a super-2 number, since 2×51113255520² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51113255527) 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, 1719504 + ... + 1748976.

It is an arithmetic number, because the mean of its divisors is an integer number (1677674817).

Almost surely, 2^51113255520 is an apocalyptic number.

It is an amenable number.

51113255520 is an abundant number, since it is smaller than the sum of its proper divisors (109943526912).

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

51113255520 is a wasteful number, since it uses less digits than its factorization.

51113255520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33104 (or 33096 counting only the distinct ones).

The product of its (nonzero) digits is 7500, while the sum is 30.

Adding to 51113255520 its reverse (2555231115), we get a palindrome (53668486635).

The spelling of 51113255520 in words is "fifty-one billion, one hundred thirteen million, two hundred fifty-five thousand, five hundred twenty".