21120835 has 4 divisors (see below), whose sum is σ = 25345008. Its totient is φ = 16896664.

The previous prime is 21120833. The next prime is 21120893. The reversal of 21120835 is 53802112.

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 21120835 - 2¹ = 21120833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21120833) 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, 2112079 + ... + 2112088.

It is an arithmetic number, because the mean of its divisors is an integer number (6336252).

Almost surely, 2^21120835 is an apocalyptic number.

21120835 is a deficient number, since it is larger than the sum of its proper divisors (4224173).

21120835 is an equidigital number, since it uses as much as digits as its factorization.

21120835 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4224172.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 21120835 is about 4595.7409631092. The cubic root of 21120835 is about 276.4205719576.

Adding to 21120835 its reverse (53802112), we get a palindrome (74922947).

The spelling of 21120835 in words is "twenty-one million, one hundred twenty thousand, eight hundred thirty-five".