21923738 has 8 divisors (see below), whose sum is σ = 34315488. Its totient is φ = 10485244.

The previous prime is 21923731. The next prime is 21923747. The reversal of 21923738 is 83732912.

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

It is a junction number, because it is equal to n+sod(n) for n = 21923698 and 21923707.

It is not an unprimeable number, because it can be changed into a prime (21923731) 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 3 ways as a sum of consecutive naturals, for example, 238256 + ... + 238347.

It is an arithmetic number, because the mean of its divisors is an integer number (4289436).

Almost surely, 2^21923738 is an apocalyptic number.

21923738 is a deficient number, since it is larger than the sum of its proper divisors (12391750).

21923738 is a wasteful number, since it uses less digits than its factorization.

21923738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476628.

The product of its digits is 18144, while the sum is 35.

The square root of 21923738 is about 4682.2791458861. The cubic root of 21923738 is about 279.8797868313.

The spelling of 21923738 in words is "twenty-one million, nine hundred twenty-three thousand, seven hundred thirty-eight".