21706522 has 8 divisors (see below), whose sum is σ = 32724000. Its totient is φ = 10798524.

The previous prime is 21706519. The next prime is 21706523. The reversal of 21706522 is 22560712.

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

It is not an unprimeable number, because it can be changed into a prime (21706523) 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, 26872 + ... + 27667.

It is an arithmetic number, because the mean of its divisors is an integer number (4090500).

Almost surely, 2^21706522 is an apocalyptic number.

21706522 is a deficient number, since it is larger than the sum of its proper divisors (11017478).

21706522 is a wasteful number, since it uses less digits than its factorization.

21706522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54740.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 21706522 is about 4659.0258638475. The cubic root of 21706522 is about 278.9523862856.

The spelling of 21706522 in words is "twenty-one million, seven hundred six thousand, five hundred twenty-two".