2021445561 has 8 divisors (see below), whose sum is σ = 2695840000. Its totient is φ = 1347340752.

The previous prime is 2021445553. The next prime is 2021445589. The reversal of 2021445561 is 1655441202.

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

It is not a de Polignac number, because 2021445561 - 2³ = 2021445553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2021445521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55561 + ... + 84438.

It is an arithmetic number, because the mean of its divisors is an integer number (336980000).

Almost surely, 2^2021445561 is an apocalyptic number.

It is an amenable number.

2021445561 is a deficient number, since it is larger than the sum of its proper divisors (674394439).

2021445561 is a wasteful number, since it uses less digits than its factorization.

2021445561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144815.

The product of its (nonzero) digits is 9600, while the sum is 30.

The square root of 2021445561 is about 44960.4888874665. The cubic root of 2021445561 is about 1264.4083348071.

Adding to 2021445561 its reverse (1655441202), we get a palindrome (3676886763).

The spelling of 2021445561 in words is "two billion, twenty-one million, four hundred forty-five thousand, five hundred sixty-one".