21283838 has 24 divisors (see below), whose sum is σ = 34564320. Its totient is φ = 9822240.

The previous prime is 21283777. The next prime is 21283841. The reversal of 21283838 is 83838212.

It is a happy number.

21283838 is a modest number, since divided by 3838 gives 2128 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 21283798 and 21283807.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29243 + ... + 29961.

It is an arithmetic number, because the mean of its divisors is an integer number (1440180).

Almost surely, 2^21283838 is an apocalyptic number.

21283838 is a deficient number, since it is larger than the sum of its proper divisors (13280482).

21283838 is a wasteful number, since it uses less digits than its factorization.

21283838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 800 (or 781 counting only the distinct ones).

The product of its digits is 18432, while the sum is 35.

The square root of 21283838 is about 4613.4410151209. The cubic root of 21283838 is about 277.1298552272.

The spelling of 21283838 in words is "twenty-one million, two hundred eighty-three thousand, eight hundred thirty-eight".