2021785920 has 560 divisors, whose sum is σ = 8975311488. Its totient is φ = 419696640.

The previous prime is 2021785919. The next prime is 2021785957. The reversal of 2021785920 is 295871202.

It is a tau number, because it is divible by the number of its divisors (560).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1995334 + ... + 1996346.

Almost surely, 2^2021785920 is an apocalyptic number.

2021785920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2021785920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4487655744).

2021785920 is an abundant number, since it is smaller than the sum of its proper divisors (6953525568).

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

2021785920 is a wasteful number, since it uses less digits than its factorization.

2021785920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1060 (or 1041 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 2021785920 is about 44964.2738182215. The cubic root of 2021785920 is about 1264.4792953470.

The spelling of 2021785920 in words is "two billion, twenty-one million, seven hundred eighty-five thousand, nine hundred twenty".