2011855720 has 48 divisors (see below), whose sum is σ = 5265729540. Its totient is φ = 689778432.

The previous prime is 2011855711. The next prime is 2011855751. The reversal of 2011855720 is 275581102.

It can be written as a sum of positive squares in 2 ways, for example, as 1928790724 + 83064996 = 43918^2 + 9114^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 511269 + ... + 515188.

Almost surely, 2^2011855720 is an apocalyptic number.

2011855720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2011855720 is an abundant number, since it is smaller than the sum of its proper divisors (3253873820).

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

2011855720 is a wasteful number, since it uses less digits than its factorization.

2011855720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1026482 (or 1026471 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 31.

The square root of 2011855720 is about 44853.7146733690. The cubic root of 2011855720 is about 1262.4056920045.

The spelling of 2011855720 in words is "two billion, eleven million, eight hundred fifty-five thousand, seven hundred twenty".