2138512321 has 16 divisors (see below), whose sum is σ = 2353938048. Its totient is φ = 1926662400.

The previous prime is 2138512309. The next prime is 2138512351. The reversal of 2138512321 is 1232158312.

It is a cyclic number.

It is not a de Polignac number, because 2138512321 - 2²³ = 2130123713 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2138512321.

It is not an unprimeable number, because it can be changed into a prime (2138512351) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 683641 + ... + 686761.

It is an arithmetic number, because the mean of its divisors is an integer number (147121128).

Almost surely, 2^2138512321 is an apocalyptic number.

It is an amenable number.

2138512321 is a deficient number, since it is larger than the sum of its proper divisors (215425727).

2138512321 is a wasteful number, since it uses less digits than its factorization.

2138512321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3672.

The product of its digits is 2880, while the sum is 28.

The square root of 2138512321 is about 46244.0517364125. The cubic root of 2138512321 is about 1288.3600579681.

The spelling of 2138512321 in words is "two billion, one hundred thirty-eight million, five hundred twelve thousand, three hundred twenty-one".