2106671778 has 48 divisors (see below), whose sum is σ = 4812475200. Its totient is φ = 664187040.

The previous prime is 2106671659. The next prime is 2106671779. The reversal of 2106671778 is 8771766012.

It is not an unprimeable number, because it can be changed into a prime (2106671779) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 221403 + ... + 230721.

It is an arithmetic number, because the mean of its divisors is an integer number (100259900).

Almost surely, 2^2106671778 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2106671778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2406237600).

2106671778 is an abundant number, since it is smaller than the sum of its proper divisors (2705803422).

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

2106671778 is a wasteful number, since it uses less digits than its factorization.

2106671778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10007 (or 10004 counting only the distinct ones).

The product of its (nonzero) digits is 197568, while the sum is 45.

The square root of 2106671778 is about 45898.4942890287. The cubic root of 2106671778 is about 1281.9338805288.

The spelling of 2106671778 in words is "two billion, one hundred six million, six hundred seventy-one thousand, seven hundred seventy-eight".