21789801 has 48 divisors (see below), whose sum is σ = 36998208. Its totient is φ = 12312960.

The previous prime is 21789797. The next prime is 21789839. The reversal of 21789801 is 10898712.

It is not a de Polignac number, because 21789801 - 2² = 21789797 is a prime.

21789801 is a modest number, since divided by 9801 gives 2178 as remainder.

It is a Curzon number.

It is a zygodrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21789851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 203590 + ... + 203696.

It is an arithmetic number, because the mean of its divisors is an integer number (770796).

Almost surely, 2^21789801 is an apocalyptic number.

It is an amenable number.

21789801 is a deficient number, since it is larger than the sum of its proper divisors (15208407).

21789801 is a wasteful number, since it uses less digits than its factorization.

21789801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163 (or 138 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 36.

The square root of 21789801 is about 4667.9546912968. The cubic root of 21789801 is about 279.3086729020.

The spelling of 21789801 in words is "twenty-one million, seven hundred eighty-nine thousand, eight hundred one".