54781687 has 2 divisors, whose sum is σ = 54781688. Its totient is φ = 54781686.

The previous prime is 54781669. The next prime is 54781691. The reversal of 54781687 is 78618745.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-54781687 is a prime.

It is equal to p_3269989 and since 54781687 and 3269989 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (54781487) 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 as a sum of consecutive naturals, namely, 27390843 + 27390844.

It is an arithmetic number, because the mean of its divisors is an integer number (27390844).

Almost surely, 2^54781687 is an apocalyptic number.

54781687 is a deficient number, since it is larger than the sum of its proper divisors (1).

54781687 is an equidigital number, since it uses as much as digits as its factorization.

54781687 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 376320, while the sum is 46.

The square root of 54781687 is about 7401.4651927845. The cubic root of 54781687 is about 379.7914067553.

The spelling of 54781687 in words is "fifty-four million, seven hundred eighty-one thousand, six hundred eighty-seven".