2138105421 has 12 divisors (see below), whose sum is σ = 3171844572. Its totient is φ = 1386878976.

The previous prime is 2138105357. The next prime is 2138105447. The reversal of 2138105421 is 1245018312.

2138105421 is a `hidden beast` number, since 2 + 138 + 105 + 421 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 976250025 + 1161855396 = 31245^2 + 34086^2 .

It is not a de Polignac number, because 2138105421 - 2⁶ = 2138105357 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2138175421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3210036 + ... + 3210701.

It is an arithmetic number, because the mean of its divisors is an integer number (264320381).

Almost surely, 2^2138105421 is an apocalyptic number.

It is an amenable number.

2138105421 is a deficient number, since it is larger than the sum of its proper divisors (1033739151).

2138105421 is a wasteful number, since it uses less digits than its factorization.

2138105421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6420780 (or 6420777 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 2138105421 is about 46239.6520423759. The cubic root of 2138105421 is about 1288.2783396391.

The spelling of 2138105421 in words is "two billion, one hundred thirty-eight million, one hundred five thousand, four hundred twenty-one".