21770107 has 4 divisors (see below), whose sum is σ = 22127056. Its totient is φ = 21413160.

The previous prime is 21770093. The next prime is 21770129. The reversal of 21770107 is 70107712.

21770107 is nontrivially palindromic in base 12.

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 21770107 - 2¹¹ = 21768059 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21770407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 178383 + ... + 178504.

It is an arithmetic number, because the mean of its divisors is an integer number (5531764).

Almost surely, 2^21770107 is an apocalyptic number.

21770107 is a deficient number, since it is larger than the sum of its proper divisors (356949).

21770107 is an equidigital number, since it uses as much as digits as its factorization.

21770107 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356948.

The product of its (nonzero) digits is 686, while the sum is 25.

The square root of 21770107 is about 4665.8447252346. The cubic root of 21770107 is about 279.2244995305.

Adding to 21770107 its reverse (70107712), we get a palindrome (91877819).

The spelling of 21770107 in words is "twenty-one million, seven hundred seventy thousand, one hundred seven".