21946705 has 8 divisors (see below), whose sum is σ = 28730304. Its totient is φ = 15961200.

The previous prime is 21946703. The next prime is 21946723. The reversal of 21946705 is 50764912.

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

It is not a de Polignac number, because 21946705 - 2¹ = 21946703 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21946703) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 199461 + ... + 199570.

It is an arithmetic number, because the mean of its divisors is an integer number (3591288).

Almost surely, 2^21946705 is an apocalyptic number.

It is an amenable number.

21946705 is a deficient number, since it is larger than the sum of its proper divisors (6783599).

21946705 is a wasteful number, since it uses less digits than its factorization.

21946705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 399047.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 21946705 is about 4684.7310488437. The cubic root of 21946705 is about 279.9774854346.

The spelling of 21946705 in words is "twenty-one million, nine hundred forty-six thousand, seven hundred five".