2009373821 has 12 divisors (see below), whose sum is σ = 2517238332. Its totient is φ = 1589833728.

The previous prime is 2009373787. The next prime is 2009373829. The reversal of 2009373821 is 1283739002.

It can be written as a sum of positive squares in 2 ways, for example, as 843902500 + 1165471321 = 29050^2 + 34139^2 .

It is not a de Polignac number, because 2009373821 - 2⁶ = 2009373757 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2009373829) 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 11 ways as a sum of consecutive naturals, for example, 1576580 + ... + 1577853.

It is an arithmetic number, because the mean of its divisors is an integer number (209769861).

Almost surely, 2^2009373821 is an apocalyptic number.

It is an amenable number.

2009373821 is a deficient number, since it is larger than the sum of its proper divisors (507864511).

2009373821 is a wasteful number, since it uses less digits than its factorization.

2009373821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3154460 (or 3154453 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 35.

The square root of 2009373821 is about 44826.0395417663. The cubic root of 2009373821 is about 1261.8863617377.

The spelling of 2009373821 in words is "two billion, nine million, three hundred seventy-three thousand, eight hundred twenty-one".