54515171781 has 24 divisors (see below), whose sum is σ = 90001184000. Its totient is φ = 31148797536.

The previous prime is 54515171779. The next prime is 54515171783. The reversal of 54515171781 is 18717151545.

54515171781 is a `hidden beast` number, since 5 + 4 + 51 + 517 + 1 + 7 + 81 = 666.

It is an interprime number because it is at equal distance from previous prime (54515171779) and next prime (54515171783).

It is not a de Polignac number, because 54515171781 - 2¹ = 54515171779 is a prime.

It is a super-2 number, since 2×54515171781² (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 (54515171783) 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 23 ways as a sum of consecutive naturals, for example, 851031 + ... + 912843.

Almost surely, 2^54515171781 is an apocalyptic number.

It is an amenable number.

54515171781 is a deficient number, since it is larger than the sum of its proper divisors (35486012219).

54515171781 is a wasteful number, since it uses less digits than its factorization.

54515171781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75825 (or 75822 counting only the distinct ones).

The product of its digits is 196000, while the sum is 45.

The spelling of 54515171781 in words is "fifty-four billion, five hundred fifteen million, one hundred seventy-one thousand, seven hundred eighty-one".