21841838 has 8 divisors (see below), whose sum is σ = 34690032. Its totient is φ = 10278496.

The previous prime is 21841829. The next prime is 21841861. The reversal of 21841838 is 83814812.

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 = 21841798 and 21841807.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 321170 + ... + 321237.

It is an arithmetic number, because the mean of its divisors is an integer number (4336254).

Almost surely, 2^21841838 is an apocalyptic number.

21841838 is a deficient number, since it is larger than the sum of its proper divisors (12848194).

21841838 is a wasteful number, since it uses less digits than its factorization.

21841838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 642426.

The product of its digits is 12288, while the sum is 35.

The square root of 21841838 is about 4673.5252219283. The cubic root of 21841838 is about 279.5308384725.

The spelling of 21841838 in words is "twenty-one million, eight hundred forty-one thousand, eight hundred thirty-eight".