51530251555 has 4 divisors (see below), whose sum is σ = 61836301872. Its totient is φ = 41224201240.

The previous prime is 51530251499. The next prime is 51530251567. The reversal of 51530251555 is 55515203515.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 55515203515 = 5 ⋅11103040703.

It is not a de Polignac number, because 51530251555 - 2⁹ = 51530251043 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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, 5153025151 + ... + 5153025160.

It is an arithmetic number, because the mean of its divisors is an integer number (15459075468).

Almost surely, 2^51530251555 is an apocalyptic number.

51530251555 is a deficient number, since it is larger than the sum of its proper divisors (10306050317).

51530251555 is a wasteful number, since it uses less digits than its factorization.

51530251555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10306050316.

The product of its (nonzero) digits is 93750, while the sum is 37.

The spelling of 51530251555 in words is "fifty-one billion, five hundred thirty million, two hundred fifty-one thousand, five hundred fifty-five".