21788794 has 8 divisors (see below), whose sum is σ = 33480468. Its totient is φ = 10628640.

The previous prime is 21788771. The next prime is 21788803. The reversal of 21788794 is 49788712.

It can be written as a sum of positive squares in 2 ways, for example, as 21762225 + 26569 = 4665^2 + 163^2 .

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

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 132777 + ... + 132940.

Almost surely, 2^21788794 is an apocalyptic number.

21788794 is a deficient number, since it is larger than the sum of its proper divisors (11691674).

21788794 is a wasteful number, since it uses less digits than its factorization.

21788794 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265760.

The product of its digits is 225792, while the sum is 46.

The square root of 21788794 is about 4667.8468269642. The cubic root of 21788794 is about 279.3043701525.

The spelling of 21788794 in words is "twenty-one million, seven hundred eighty-eight thousand, seven hundred ninety-four".