21151103 has 4 divisors (see below), whose sum is σ = 21162120. Its totient is φ = 21140088.

The previous prime is 21151069. The next prime is 21151147. The reversal of 21151103 is 30115112.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21151103 - 2⁸ = 21150847 is a prime.

It is a Duffinian number.

It is a zygodrome in base 4.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21151183) 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, 1793 + ... + 6746.

It is an arithmetic number, because the mean of its divisors is an integer number (5290530).

Almost surely, 2^21151103 is an apocalyptic number.

21151103 is a deficient number, since it is larger than the sum of its proper divisors (11017).

21151103 is an equidigital number, since it uses as much as digits as its factorization.

21151103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11016.

The product of its (nonzero) digits is 30, while the sum is 14.

The square root of 21151103 is about 4599.0328331074. The cubic root of 21151103 is about 276.5525538658.

Adding to 21151103 its reverse (30115112), we get a palindrome (51266215).

The spelling of 21151103 in words is "twenty-one million, one hundred fifty-one thousand, one hundred three".