2179781604 has 540 divisors, whose sum is σ = 7916211072. Its totient is φ = 511505280.

The previous prime is 2179781603. The next prime is 2179781627. The reversal of 2179781604 is 4061879712.

It is a happy number.

2179781604 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×2179781604² = 9502895682273625632, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2179781604.

It is not an unprimeable number, because it can be changed into a prime (2179781603) by changing a digit.

It is a polite number, since it can be written in 179 ways as a sum of consecutive naturals, for example, 46378309 + ... + 46378355.

Almost surely, 2^2179781604 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 2179781604, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3958105536).

2179781604 is an abundant number, since it is smaller than the sum of its proper divisors (5736429468).

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

2179781604 is a wasteful number, since it uses less digits than its factorization.

2179781604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118 (or 83 counting only the distinct ones).

The product of its (nonzero) digits is 169344, while the sum is 45.

The square root of 2179781604 is about 46688.1312969367. The cubic root of 2179781604 is about 1296.5949557409.

The spelling of 2179781604 in words is "two billion, one hundred seventy-nine million, seven hundred eighty-one thousand, six hundred four".