21932705 has 4 divisors (see below), whose sum is σ = 26319252. Its totient is φ = 17546160.

The previous prime is 21932689. The next prime is 21932711. The reversal of 21932705 is 50723912.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13476241 + 8456464 = 3671^2 + 2908^2 .

It is not a de Polignac number, because 21932705 - 2⁴ = 21932689 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2193266 + ... + 2193275.

It is an arithmetic number, because the mean of its divisors is an integer number (6579813).

Almost surely, 2^21932705 is an apocalyptic number.

It is an amenable number.

21932705 is a deficient number, since it is larger than the sum of its proper divisors (4386547).

21932705 is an equidigital number, since it uses as much as digits as its factorization.

21932705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4386546.

The product of its (nonzero) digits is 3780, while the sum is 29.

The square root of 21932705 is about 4683.2365944932. The cubic root of 21932705 is about 279.9179393879.

The spelling of 21932705 in words is "twenty-one million, nine hundred thirty-two thousand, seven hundred five".