21685834 has 8 divisors (see below), whose sum is σ = 32557248. Its totient is φ = 10833420.

The previous prime is 21685831. The next prime is 21685837. The reversal of 21685834 is 43858612.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21685831) and next prime (21685837).

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 = 21685793 and 21685802.

It is not an unprimeable number, because it can be changed into a prime (21685831) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1432 + ... + 6739.

It is an arithmetic number, because the mean of its divisors is an integer number (4069656).

Almost surely, 2^21685834 is an apocalyptic number.

21685834 is a deficient number, since it is larger than the sum of its proper divisors (10871414).

21685834 is a wasteful number, since it uses less digits than its factorization.

21685834 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9500.

The product of its digits is 46080, while the sum is 37.

The square root of 21685834 is about 4656.8051279821. The cubic root of 21685834 is about 278.8637370257.

The spelling of 21685834 in words is "twenty-one million, six hundred eighty-five thousand, eight hundred thirty-four".