21026873 has 8 divisors (see below), whose sum is σ = 24301440. Its totient is φ = 17820000.

The previous prime is 21026869. The next prime is 21026881. The reversal of 21026873 is 37862012.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21026873 - 2² = 21026869 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21026573) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16253 + ... + 17498.

It is an arithmetic number, because the mean of its divisors is an integer number (3037680).

Almost surely, 2^21026873 is an apocalyptic number.

It is an amenable number.

21026873 is a deficient number, since it is larger than the sum of its proper divisors (3274567).

21026873 is an equidigital number, since it uses as much as digits as its factorization.

21026873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33847.

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 21026873 is about 4585.5068422149. The cubic root of 21026873 is about 276.0100509187.

Adding to 21026873 its reverse (37862012), we get a palindrome (58888885).

The spelling of 21026873 in words is "twenty-one million, twenty-six thousand, eight hundred seventy-three".