2005546021 has 6 divisors (see below), whose sum is σ = 2009753522. Its totient is φ = 2001347280.

The previous prime is 2005546003. The next prime is 2005546033. The reversal of 2005546021 is 1206455002.

It can be written as a sum of positive squares in 3 ways, for example, as 590733025 + 1414812996 = 24305^2 + 37614^2 .

It is not a de Polignac number, because 2005546021 - 2⁵ = 2005545989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2005546051) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 255211 + ... + 262951.

Almost surely, 2^2005546021 is an apocalyptic number.

It is an amenable number.

2005546021 is a deficient number, since it is larger than the sum of its proper divisors (4207501).

2005546021 is an frugal number, since it uses more digits than its factorization.

2005546021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8759 (or 8250 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 2005546021 is about 44783.3230231969. The cubic root of 2005546021 is about 1261.0845665089.

The spelling of 2005546021 in words is "two billion, five million, five hundred forty-six thousand, twenty-one".