21302055 has 16 divisors (see below), whose sum is σ = 37870560. Its totient is φ = 11361024.

The previous prime is 21302051. The next prime is 21302063. The reversal of 21302055 is 55020312.

It is a happy number.

It is not a de Polignac number, because 21302055 - 2² = 21302051 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21302051) 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 15 ways as a sum of consecutive naturals, for example, 78762 + ... + 79031.

It is an arithmetic number, because the mean of its divisors is an integer number (2366910).

Almost surely, 2^21302055 is an apocalyptic number.

21302055 is a deficient number, since it is larger than the sum of its proper divisors (16568505).

21302055 is a wasteful number, since it uses less digits than its factorization.

21302055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157807 (or 157801 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 18.

The square root of 21302055 is about 4615.4149325927. The cubic root of 21302055 is about 277.2088985356.

Adding to 21302055 its reverse (55020312), we get a palindrome (76322367).

The spelling of 21302055 in words is "twenty-one million, three hundred two thousand, fifty-five".