21104153 has 6 divisors (see below), whose sum is σ = 24549786. Its totient is φ = 18089232.

The previous prime is 21104143. The next prime is 21104203. The reversal of 21104153 is 35140112.

It can be written as a sum of positive squares in only one way, i.e., 21086464 + 17689 = 4592^2 + 133^2 .

It is not a de Polignac number, because 21104153 - 2⁸ = 21103897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21104143) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 215300 + ... + 215397.

It is an arithmetic number, because the mean of its divisors is an integer number (4091631).

Almost surely, 2^21104153 is an apocalyptic number.

It is an amenable number.

21104153 is a deficient number, since it is larger than the sum of its proper divisors (3445633).

21104153 is an equidigital number, since it uses as much as digits as its factorization.

21104153 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430711 (or 430704 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 21104153 is about 4593.9256633080. The cubic root of 21104153 is about 276.3477771311.

Adding to 21104153 its reverse (35140112), we get a palindrome (56244265).

The spelling of 21104153 in words is "twenty-one million, one hundred four thousand, one hundred fifty-three".