21005348438344 has 8 divisors (see below), whose sum is σ = 39385028321910. Its totient is φ = 10502674219168.

The previous prime is 21005348438297. The next prime is 21005348438351. The reversal of 21005348438344 is 44383484350012.

It can be written as a sum of positive squares in only one way, i.e., 20707614515844 + 297733922500 = 4550562^2 + 545650^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-3 number, since 3×21005348438344³ (a number of 41 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1312834277389 + ... + 1312834277404.

Almost surely, 2^{21005348438344} is an apocalyptic number.

It is an amenable number.

21005348438344 is a deficient number, since it is larger than the sum of its proper divisors (18379679883566).

21005348438344 is a wasteful number, since it uses less digits than its factorization.

21005348438344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2625668554799 (or 2625668554795 counting only the distinct ones).

The product of its (nonzero) digits is 4423680, while the sum is 49.

The spelling of 21005348438344 in words is "twenty-one trillion, five billion, three hundred forty-eight million, four hundred thirty-eight thousand, three hundred forty-four".