51720722493 has 64 divisors (see below), whose sum is σ = 78479622144. Its totient is φ = 30015288000.

The previous prime is 51720722483. The next prime is 51720722503. The reversal of 51720722493 is 39422702715.

It is an interprime number because it is at equal distance from previous prime (51720722483) and next prime (51720722503).

It is not a de Polignac number, because 51720722493 - 2⁸ = 51720722237 is a prime.

It is a super-2 number, since 2×51720722493² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51720722483) 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 63 ways as a sum of consecutive naturals, for example, 43572046 + ... + 43573232.

It is an arithmetic number, because the mean of its divisors is an integer number (1226244096).

Almost surely, 2^51720722493 is an apocalyptic number.

It is an amenable number.

51720722493 is a deficient number, since it is larger than the sum of its proper divisors (26758899651).

51720722493 is a wasteful number, since it uses less digits than its factorization.

51720722493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1646.

The product of its (nonzero) digits is 211680, while the sum is 42.

The spelling of 51720722493 in words is "fifty-one billion, seven hundred twenty million, seven hundred twenty-two thousand, four hundred ninety-three".