21133055 has 4 divisors (see below), whose sum is σ = 25359672. Its totient is φ = 16906440.

The previous prime is 21133027. The next prime is 21133087. The reversal of 21133055 is 55033112.

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

It is not a de Polignac number, because 21133055 - 2¹² = 21128959 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2113301 + ... + 2113310.

It is an arithmetic number, because the mean of its divisors is an integer number (6339918).

Almost surely, 2^21133055 is an apocalyptic number.

21133055 is a deficient number, since it is larger than the sum of its proper divisors (4226617).

21133055 is an equidigital number, since it uses as much as digits as its factorization.

21133055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4226616.

The product of its (nonzero) digits is 450, while the sum is 20.

The square root of 21133055 is about 4597.0702626782. The cubic root of 21133055 is about 276.4738717467.

Adding to 21133055 its reverse (55033112), we get a palindrome (76166167).

The spelling of 21133055 in words is "twenty-one million, one hundred thirty-three thousand, fifty-five".