2891138688 has 96 divisors (see below), whose sum is σ = 8331735360. Its totient is φ = 962302464.

The previous prime is 2891138687. The next prime is 2891138693. The reversal of 2891138688 is 8868311982.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×2891138688² = 16717365826500722688, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (2891138687) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1043481 + ... + 1046247.

It is an arithmetic number, because the mean of its divisors is an integer number (86788910).

Almost surely, 2^2891138688 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 2891138688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4165867680).

2891138688 is an abundant number, since it is smaller than the sum of its proper divisors (5440596672).

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

2891138688 is a wasteful number, since it uses less digits than its factorization.

2891138688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3694 (or 3679 counting only the distinct ones).

The product of its digits is 1327104, while the sum is 54.

The square root of 2891138688 is about 53769.3099081623. The cubic root of 2891138688 is about 1424.5891809283.

The spelling of 2891138688 in words is "two billion, eight hundred ninety-one million, one hundred thirty-eight thousand, six hundred eighty-eight".