21606834 has 8 divisors (see below), whose sum is σ = 43213680. Its totient is φ = 7202276.

The previous prime is 21606817. The next prime is 21606839. The reversal of 21606834 is 43860612.

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

21606834 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (21606839) 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, 1800564 + ... + 1800575.

It is an arithmetic number, because the mean of its divisors is an integer number (5401710).

Almost surely, 2^21606834 is an apocalyptic number.

21606834 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21606834 is a wasteful number, since it uses less digits than its factorization.

21606834 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3601144.

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 21606834 is about 4648.3151786427. The cubic root of 21606834 is about 278.5246978624.

The spelling of 21606834 in words is "twenty-one million, six hundred six thousand, eight hundred thirty-four".