21784736055 has 32 divisors (see below), whose sum is σ = 36180768960. Its totient is φ = 11179535360.

The previous prime is 21784736053. The next prime is 21784736093. The reversal of 21784736055 is 55063748712.

It is not a de Polignac number, because 21784736055 - 2¹ = 21784736053 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21784735995 and 21784736013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21784736053) 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 31 ways as a sum of consecutive naturals, for example, 41995 + ... + 212915.

It is an arithmetic number, because the mean of its divisors is an integer number (1130649030).

Almost surely, 2^21784736055 is an apocalyptic number.

21784736055 is a deficient number, since it is larger than the sum of its proper divisors (14396032905).

21784736055 is a wasteful number, since it uses less digits than its factorization.

21784736055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171251.

The product of its (nonzero) digits is 1411200, while the sum is 48.

The spelling of 21784736055 in words is "twenty-one billion, seven hundred eighty-four million, seven hundred thirty-six thousand, fifty-five".