21701443 has 4 divisors (see below), whose sum is σ = 22645008. Its totient is φ = 20757880.

The previous prime is 21701441. The next prime is 21701447. The reversal of 21701443 is 34410712.

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

It is a cyclic number.

It is not a de Polignac number, because 21701443 - 2¹ = 21701441 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21701441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 471748 + ... + 471793.

It is an arithmetic number, because the mean of its divisors is an integer number (5661252).

Almost surely, 2^21701443 is an apocalyptic number.

21701443 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21701443 is a deficient number, since it is larger than the sum of its proper divisors (943565).

21701443 is an equidigital number, since it uses as much as digits as its factorization.

21701443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 943564.

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 21701443 is about 4658.4807609348. The cubic root of 21701443 is about 278.9306276994.

The spelling of 21701443 in words is "twenty-one million, seven hundred one thousand, four hundred forty-three".