21941065447 has 8 divisors (see below), whose sum is σ = 25334014496. Its totient is φ = 18612744192.

The previous prime is 21941065409. The next prime is 21941065457. The reversal of 21941065447 is 74456014912.

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

It is not a de Polignac number, because 21941065447 - 2¹⁹ = 21940541159 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21941065457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16156218 + ... + 16157575.

It is an arithmetic number, because the mean of its divisors is an integer number (3166751812).

Almost surely, 2^21941065447 is an apocalyptic number.

21941065447 is a deficient number, since it is larger than the sum of its proper divisors (3392949049).

21941065447 is an equidigital number, since it uses as much as digits as its factorization.

21941065447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32313897.

The product of its (nonzero) digits is 241920, while the sum is 43.

The spelling of 21941065447 in words is "twenty-one billion, nine hundred forty-one million, sixty-five thousand, four hundred forty-seven".