21026288 has 10 divisors (see below), whose sum is σ = 40738464. Its totient is φ = 10513136.

The previous prime is 21026287. The next prime is 21026303. The reversal of 21026288 is 88262012.

It is a self number, because there is not a number n which added to its sum of digits gives 21026288.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21026287) 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 as a sum of consecutive naturals, namely, 657056 + ... + 657087.

Almost surely, 2^21026288 is an apocalyptic number.

It is an amenable number.

21026288 is a deficient number, since it is larger than the sum of its proper divisors (19712176).

21026288 is a wasteful number, since it uses less digits than its factorization.

21026288 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1314151 (or 1314145 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 29.

The square root of 21026288 is about 4585.4430538390. The cubic root of 21026288 is about 276.0074912200.

The spelling of 21026288 in words is "twenty-one million, twenty-six thousand, two hundred eighty-eight".