51515145223 has 4 divisors (see below), whose sum is σ = 52015292368. Its totient is φ = 51014998080.

The previous prime is 51515145179. The next prime is 51515145263. The reversal of 51515145223 is 32254151515.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32254151515 = 5 ⋅6450830303.

It is a cyclic number.

It is not a de Polignac number, because 51515145223 - 2⁹ = 51515144711 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51515145263) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 250073418 + ... + 250073623.

It is an arithmetic number, because the mean of its divisors is an integer number (13003823092).

Almost surely, 2^51515145223 is an apocalyptic number.

51515145223 is a deficient number, since it is larger than the sum of its proper divisors (500147145).

51515145223 is a wasteful number, since it uses less digits than its factorization.

51515145223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500147144.

The product of its digits is 30000, while the sum is 34.

Adding to 51515145223 its reverse (32254151515), we get a palindrome (83769296738).

The spelling of 51515145223 in words is "fifty-one billion, five hundred fifteen million, one hundred forty-five thousand, two hundred twenty-three".