21005348438338 has 12 divisors (see below), whose sum is σ = 34632785235510. Its totient is φ = 9547885653680.

The previous prime is 21005348438297. The next prime is 21005348438351. The reversal of 21005348438338 is 83383484350012.

It can be written as a sum of positive squares in only one way, i.e., 20523772120489 + 481576317849 = 4530317^2 + 693957^2 .

It is a super-3 number, since 3×21005348438338³ (a number of 41 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 43399480003 + ... + 43399480486.

Almost surely, 2^{21005348438338} is an apocalyptic number.

21005348438338 is a deficient number, since it is larger than the sum of its proper divisors (13627436797172).

21005348438338 is a wasteful number, since it uses less digits than its factorization.

21005348438338 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86798960513 (or 86798960502 counting only the distinct ones).

The product of its (nonzero) digits is 6635520, while the sum is 52.

The spelling of 21005348438338 in words is "twenty-one trillion, five billion, three hundred forty-eight million, four hundred thirty-eight thousand, three hundred thirty-eight".