2021989447 has 2 divisors, whose sum is σ = 2021989448. Its totient is φ = 2021989446.

The previous prime is 2021989433. The next prime is 2021989471. The reversal of 2021989447 is 7449891202.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2021989447 - 2¹¹ = 2021987399 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2021989397 and 2021989406.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2021989147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1010994723 + 1010994724.

It is an arithmetic number, because the mean of its divisors is an integer number (1010994724).

Almost surely, 2^2021989447 is an apocalyptic number.

2021989447 is a deficient number, since it is larger than the sum of its proper divisors (1).

2021989447 is an equidigital number, since it uses as much as digits as its factorization.

2021989447 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 290304, while the sum is 46.

The square root of 2021989447 is about 44966.5369691730. The cubic root of 2021989447 is about 1264.5217243434.

The spelling of 2021989447 in words is "two billion, twenty-one million, nine hundred eighty-nine thousand, four hundred forty-seven".