21770027 has 4 divisors (see below), whose sum is σ = 21784056. Its totient is φ = 21756000.

The previous prime is 21770017. The next prime is 21770033. The reversal of 21770027 is 72007712.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21770027 - 2⁴ = 21770011 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21769978 and 21770005.

It is not an unprimeable number, because it can be changed into a prime (21770017) 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 3 ways as a sum of consecutive naturals, for example, 4349 + ... + 7902.

It is an arithmetic number, because the mean of its divisors is an integer number (5446014).

Almost surely, 2^21770027 is an apocalyptic number.

21770027 is a deficient number, since it is larger than the sum of its proper divisors (14029).

21770027 is a wasteful number, since it uses less digits than its factorization.

21770027 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14028.

The product of its (nonzero) digits is 1372, while the sum is 26.

The square root of 21770027 is about 4665.8361522882. The cubic root of 21770027 is about 279.2241575020.

Adding to 21770027 its reverse (72007712), we get a palindrome (93777739).

The spelling of 21770027 in words is "twenty-one million, seven hundred seventy thousand, twenty-seven".