21026153 has 16 divisors (see below), whose sum is σ = 22643712. Its totient is φ = 19488000.

The previous prime is 21026149. The next prime is 21026171. The reversal of 21026153 is 35162012.

It is a cyclic number.

It is not a de Polignac number, because 21026153 - 2² = 21026149 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21026143) 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 15 ways as a sum of consecutive naturals, for example, 90125 + ... + 90357.

It is an arithmetic number, because the mean of its divisors is an integer number (1415232).

Almost surely, 2^21026153 is an apocalyptic number.

It is an amenable number.

21026153 is a deficient number, since it is larger than the sum of its proper divisors (1617559).

21026153 is a wasteful number, since it uses less digits than its factorization.

21026153 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 376.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 21026153 is about 4585.4283333185. The cubic root of 21026153 is about 276.0069005136.

Adding to 21026153 its reverse (35162012), we get a palindrome (56188165).

The spelling of 21026153 in words is "twenty-one million, twenty-six thousand, one hundred fifty-three".