21776055 has 64 divisors (see below), whose sum is σ = 42467328. Its totient is φ = 9313920.

The previous prime is 21776039. The next prime is 21776059. The reversal of 21776055 is 55067712.

It is not a de Polignac number, because 21776055 - 2⁴ = 21776039 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21776059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 171402 + ... + 171528.

It is an arithmetic number, because the mean of its divisors is an integer number (663552).

Almost surely, 2^21776055 is an apocalyptic number.

21776055 is a deficient number, since it is larger than the sum of its proper divisors (20691273).

21776055 is a wasteful number, since it uses less digits than its factorization.

21776055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 236.

The product of its (nonzero) digits is 14700, while the sum is 33.

The square root of 21776055 is about 4666.4820796827. The cubic root of 21776055 is about 279.2499269983.

The spelling of 21776055 in words is "twenty-one million, seven hundred seventy-six thousand, fifty-five".