51721265323 has 16 divisors (see below), whose sum is σ = 64956068800. Its totient is φ = 40922316288.

The previous prime is 51721265317. The next prime is 51721265329. The reversal of 51721265323 is 32356212715.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (51721265317) and next prime (51721265329).

It is not a de Polignac number, because 51721265323 - 2⁹ = 51721264811 is a prime.

It is a super-2 number, since 2×51721265323² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (51721265329) 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, 5795190 + ... + 5804107.

It is an arithmetic number, because the mean of its divisors is an integer number (4059754300).

Almost surely, 2^51721265323 is an apocalyptic number.

51721265323 is a deficient number, since it is larger than the sum of its proper divisors (13234803477).

51721265323 is a wasteful number, since it uses less digits than its factorization.

51721265323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11599331 (or 11599317 counting only the distinct ones).

The product of its digits is 75600, while the sum is 37.

The spelling of 51721265323 in words is "fifty-one billion, seven hundred twenty-one million, two hundred sixty-five thousand, three hundred twenty-three".