4209991020 has 108 divisors (see below), whose sum is σ = 12992353920. Its totient is φ = 1103471808.

The previous prime is 4209991013. The next prime is 4209991043. The reversal of 4209991020 is 201999024.

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 35 ways as a sum of consecutive naturals, for example, 623221 + ... + 629939.

Almost surely, 2^4209991020 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 4209991020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6496176960).

4209991020 is an abundant number, since it is smaller than the sum of its proper divisors (8782362900).

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

4209991020 is a wasteful number, since it uses less digits than its factorization.

4209991020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6852 (or 6788 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 4209991020 is about 64884.4435901241. The cubic root of 4209991020 is about 1614.7069819559.

The spelling of 4209991020 in words is "four billion, two hundred nine million, nine hundred ninety-one thousand, twenty".