21798026 has 8 divisors (see below), whose sum is σ = 32954880. Its totient is φ = 10813068.

The previous prime is 21798017. The next prime is 21798047. The reversal of 21798026 is 62089712.

It is a happy number.

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

It is a Curzon number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 42656 + ... + 43163.

It is an arithmetic number, because the mean of its divisors is an integer number (4119360).

Almost surely, 2^21798026 is an apocalyptic number.

21798026 is a deficient number, since it is larger than the sum of its proper divisors (11156854).

21798026 is a wasteful number, since it uses less digits than its factorization.

21798026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85948.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 21798026 is about 4668.8356150115. The cubic root of 21798026 is about 279.3438120456.

The spelling of 21798026 in words is "twenty-one million, seven hundred ninety-eight thousand, twenty-six".