21022055 has 8 divisors (see below), whose sum is σ = 25813392. Its totient is φ = 16426368.

The previous prime is 21022051. The next prime is 21022063. The reversal of 21022055 is 55022012.

21022055 = T₇₂ + T₇₃ + ... + T₅₀₁.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21022055 - 2² = 21022051 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21022051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48674 + ... + 49103.

It is an arithmetic number, because the mean of its divisors is an integer number (3226674).

Almost surely, 2^21022055 is an apocalyptic number.

21022055 is a deficient number, since it is larger than the sum of its proper divisors (4791337).

21022055 is an equidigital number, since it uses as much as digits as its factorization.

21022055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97825.

The product of its (nonzero) digits is 200, while the sum is 17.

The square root of 21022055 is about 4584.9814612493. The cubic root of 21022055 is about 275.9889680881.

Adding to 21022055 its reverse (55022012), we get a palindrome (76044067).

The spelling of 21022055 in words is "twenty-one million, twenty-two thousand, fifty-five".