26800021 has 4 divisors (see below), whose sum is σ = 26812192. Its totient is φ = 26787852.

The previous prime is 26800009. The next prime is 26800043. The reversal of 26800021 is 12000862.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 12000862 = 2 ⋅6000431.

It is a cyclic number.

It is not a de Polignac number, because 26800021 - 2⁵ = 26799989 is a prime.

It is a super-2 number, since 2×26800021² = 1436482251200882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26800091) 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, 1755 + ... + 7528.

It is an arithmetic number, because the mean of its divisors is an integer number (6703048).

Almost surely, 2^26800021 is an apocalyptic number.

It is an amenable number.

26800021 is a deficient number, since it is larger than the sum of its proper divisors (12171).

26800021 is an equidigital number, since it uses as much as digits as its factorization.

26800021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12170.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 26800021 is about 5176.8736704695. The cubic root of 26800021 is about 299.2575008699.

Adding to 26800021 its reverse (12000862), we get a palindrome (38800883).

The spelling of 26800021 in words is "twenty-six million, eight hundred thousand, twenty-one".