21801794 has 16 divisors (see below), whose sum is σ = 38664000. Its totient is φ = 9021264.

The previous prime is 21801743. The next prime is 21801811. The reversal of 21801794 is 49710812.

It is a self number, because there is not a number n which added to its sum of digits gives 21801794.

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 7 ways as a sum of consecutive naturals, for example, 26444 + ... + 27255.

It is an arithmetic number, because the mean of its divisors is an integer number (2416500).

Almost surely, 2^21801794 is an apocalyptic number.

21801794 is a deficient number, since it is larger than the sum of its proper divisors (16862206).

21801794 is a wasteful number, since it uses less digits than its factorization.

21801794 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53737.

The product of its (nonzero) digits is 4032, while the sum is 32.

The square root of 21801794 is about 4669.2391243114. The cubic root of 21801794 is about 279.3599068798.

The spelling of 21801794 in words is "twenty-one million, eight hundred one thousand, seven hundred ninety-four".