4021644816 has 400 divisors, whose sum is σ = 13863696000. Its totient is φ = 1124782848.

The previous prime is 4021644799. The next prime is 4021644821. The reversal of 4021644816 is 6184461204.

It is a happy number.

4021644816 is a `hidden beast` number, since 4 + 0 + 2 + 1 + 644 + 8 + 1 + 6 = 666.

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

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, 36895770 + ... + 36895878.

It is an arithmetic number, because the mean of its divisors is an integer number (34659240).

Almost surely, 2^4021644816 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 4021644816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6931848000).

4021644816 is an abundant number, since it is smaller than the sum of its proper divisors (9842051184).

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

4021644816 is a wasteful number, since it uses less digits than its factorization.

4021644816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233 (or 204 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 4021644816 is about 63416.4396351608. The cubic root of 4021644816 is about 1590.2591532017.

The spelling of 4021644816 in words is "four billion, twenty-one million, six hundred forty-four thousand, eight hundred sixteen".