21442069547 has 4 divisors (see below), whose sum is σ = 21450921360. Its totient is φ = 21433217736.

The previous prime is 21442069529. The next prime is 21442069559. The reversal of 21442069547 is 74596024412.

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 21442069547 - 2⁶ = 21442069483 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21442069498 and 21442069507.

It is not an unprimeable number, because it can be changed into a prime (21442069147) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4422272 + ... + 4427117.

It is an arithmetic number, because the mean of its divisors is an integer number (5362730340).

Almost surely, 2^21442069547 is an apocalyptic number.

21442069547 is a deficient number, since it is larger than the sum of its proper divisors (8851813).

21442069547 is an equidigital number, since it uses as much as digits as its factorization.

21442069547 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8851812.

The product of its (nonzero) digits is 483840, while the sum is 44.

The spelling of 21442069547 in words is "twenty-one billion, four hundred forty-two million, sixty-nine thousand, five hundred forty-seven".