51511444551 has 24 divisors (see below), whose sum is σ = 85060520064. Its totient is φ = 29426196240.

The previous prime is 51511444519. The next prime is 51511444573. The reversal of 51511444551 is 15544411515.

51511444551 is a `hidden beast` number, since 5 + 1 + 51 + 14 + 44 + 551 = 666.

It is not a de Polignac number, because 51511444551 - 2⁵ = 51511444519 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51511444051) 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 23 ways as a sum of consecutive naturals, for example, 88716 + ... + 333006.

It is an arithmetic number, because the mean of its divisors is an integer number (3544188336).

Almost surely, 2^51511444551 is an apocalyptic number.

51511444551 is a deficient number, since it is larger than the sum of its proper divisors (33549075513).

51511444551 is a wasteful number, since it uses less digits than its factorization.

51511444551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 247651 (or 247648 counting only the distinct ones).

The product of its digits is 40000, while the sum is 36.

The spelling of 51511444551 in words is "fifty-one billion, five hundred eleven million, four hundred forty-four thousand, five hundred fifty-one".