21451153 has 4 divisors (see below), whose sum is σ = 21480768. Its totient is φ = 21421540.

The previous prime is 21451151. The next prime is 21451201. The reversal of 21451153 is 35115412.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21451153 - 2¹ = 21451151 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21451151) 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 3 ways as a sum of consecutive naturals, for example, 13693 + ... + 15178.

It is an arithmetic number, because the mean of its divisors is an integer number (5370192).

Almost surely, 2^21451153 is an apocalyptic number.

It is an amenable number.

21451153 is a deficient number, since it is larger than the sum of its proper divisors (29615).

21451153 is an equidigital number, since it uses as much as digits as its factorization.

21451153 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29614.

The product of its digits is 600, while the sum is 22.

The square root of 21451153 is about 4631.5389451024. The cubic root of 21451153 is about 277.8541451482.

Adding to 21451153 its reverse (35115412), we get a palindrome (56566565).

The spelling of 21451153 in words is "twenty-one million, four hundred fifty-one thousand, one hundred fifty-three".