2138406564 has 96 divisors (see below), whose sum is σ = 5981552640. Its totient is φ = 581772672.

The previous prime is 2138406563. The next prime is 2138406653. The reversal of 2138406564 is 4656048312.

It is not an unprimeable number, because it can be changed into a prime (2138406563) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 138757 + ... + 153395.

It is an arithmetic number, because the mean of its divisors is an integer number (62307840).

Almost surely, 2^2138406564 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 2138406564, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2990776320).

2138406564 is an abundant number, since it is smaller than the sum of its proper divisors (3843146076).

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

2138406564 is a wasteful number, since it uses less digits than its factorization.

2138406564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14737 (or 14735 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 39.

The square root of 2138406564 is about 46242.9082562937. The cubic root of 2138406564 is about 1288.3388196304.

The spelling of 2138406564 in words is "two billion, one hundred thirty-eight million, four hundred six thousand, five hundred sixty-four".