2009781456 has 40 divisors (see below), whose sum is σ = 5219142144. Its totient is φ = 666416640.

The previous prime is 2009781421. The next prime is 2009781467. The reversal of 2009781456 is 6541879002.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 100441 + ... + 118776.

Almost surely, 2^2009781456 is an apocalyptic number.

It is an amenable number.

2009781456 is an abundant number, since it is smaller than the sum of its proper divisors (3209360688).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2009781456 is a wasteful number, since it uses less digits than its factorization.

2009781456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 219419 (or 219413 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 42.

The square root of 2009781456 is about 44830.5861661433. The cubic root of 2009781456 is about 1261.9716875345.

The spelling of 2009781456 in words is "two billion, nine million, seven hundred eighty-one thousand, four hundred fifty-six".