51128521771 has 4 divisors (see below), whose sum is σ = 51434680752. Its totient is φ = 50822362792.

The previous prime is 51128521753. The next prime is 51128521781. The reversal of 51128521771 is 17712582115.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51128521771 - 2⁵ = 51128521739 is a prime.

It is a super-2 number, since 2×51128521771² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51128521711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 153079240 + ... + 153079573.

It is an arithmetic number, because the mean of its divisors is an integer number (12858670188).

Almost surely, 2^51128521771 is an apocalyptic number.

51128521771 is a deficient number, since it is larger than the sum of its proper divisors (306158981).

51128521771 is a wasteful number, since it uses less digits than its factorization.

51128521771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306158980.

The product of its digits is 39200, while the sum is 40.

The spelling of 51128521771 in words is "fifty-one billion, one hundred twenty-eight million, five hundred twenty-one thousand, seven hundred seventy-one".